Renal immunolocalization of kallikrein in cisplatin nephrotoxicity in rats

Summary Treatment of rats with cisplatin (4 mg kg^-1body wt i.p. injection) induced variations of urinary kallikrein excretion (UKE). Three phases were observed: a transient increase of UKE one day after injection, followed by a decrease up to 10 days suggesting an altered biosynthesis and a recovery phase with return to normal control values, 21 days after injection. Early morphological lesions were observed in proximal tubule cells on day 1; severe changes and tubular necrosis were observed in the following days. Less marked changes were also present in distal tubules but the vacuolated and desquamated cells appeared in the lumen of the tubules. By immunocytochemical methods, kallikrein was observed in connecting tubule cells, but also in some proximal tubule cells and along the endothelial side of the glomerular basement membrane and urinary space of glomeruli. An intense labelling was present in desquamated epithelial cells in dilated lumen of tubules. This study provides evidence of the presence of immunoreactive kallikrein in the glomerulus, already reported during acute failure, and confirms the use of urinary kallikrein measurements as a useful non-invasive index to assess a possible nephrotoxic effect at the distal level.     

Pharmacological blockade of the nephrotoxicity of cisplatin in rats

Cisplatin injection (0.5 mg/100 g body weight) induced 5 days later an increase in serum urea concentration from 3.31 +/- 0.67 to 47.1 +/- 8.68 mg/ml and diuresis decrease following water loading test. Ethacrynic acid, furosemide, paraaminohippurate pre-injections prevented cisplatin nephrotoxicity. The decrease in cisplatin nephrotoxicity took place when furosemide was administered before or 3 h after cisplatin injection; 6 h after cisplatin injection furosemide was not effective. The results suggest that pharmacological blockade of cisplatin nephrotoxicity depends on the drug penetration into secreting cells of proximal tubules.     

Tissue injury and proliferative response induced in rat kidney by cis-diamminedichloroplatinum (II)

Cis-diamminedichloroplatinum (II) (cisplatin), an inorganic platinum salt used in cancer chemotherapy, is characterized by a renal toxicity recognized both in experimental animals and in patients treated with the compound. The purpose of the present study was to explore by both light and electron microscopy the morphological alterations induced in the rat kidney by cisplatin administration and, in particular, to analyse the tissue repair reaction following nephrotoxic injury. Experimental animals (four rats per group) were treated i.p. with 2, 4 or 8 mg/kg cisplatin administered in four consecutive daily injections. The rats were sacrificed 4 days after the last injection. In addition, the persistence of renal lesions and the duration of the repair reaction were determined in rats given 8 mg/kg cisplatin and killed 4, 7, 14 or 21 days after the last injection. The cell proliferation associated with tissue repair was estimated both quantitatively (rate of DNA synthesis) and qualitatively (histoautoradiography and electron microscopy examination) 1 h after in vivo exposure to [3H] thymidine. Renal tissue alterations and the repair reaction were minimal after the administration of 2 or 4 mg/kg cisplatin. In contrast, 8 mg/kg cisplatin caused a spectrum of morphological abnormalities affecting proximal, distal and collecting tubules, and ranging from sublethal cell alterations to tubular necrosis and cystic dilatation. The latter degenerative change primarily involved the straight portion of proximal tubules and seemed to develop over the weeks following cisplatin administration. Concomitantly with the tissue lesions, a burst of cell proliferation, associated with stimulation of DNA synthesis, was apparent in the renal cortex and outer medulla. Whereas a very high incidence of S-phase cells was encountered in seemingly undifferentiated tubules, they also appeared in differentiated proximal, distal and collecting tubules, but were infrequent in cystic tubules. Proliferation of fibroblasts was also stimulated in the renal interstitium. The proliferative response persisted for the whole duration of the experiment, indicating incomplete tissue repair. The long-lasting tubular injury and the slowness of repair are consistent with the chronic renal dysfunction (polyuria and hypomagnesemia) that cisplatin is known to induce in both man and experimental animals.     

Differences in the incorporation of L- and DL-Amino acids into renal tubular cells. An autoradiographic study.

The cytoplasmic uptake of 3H-L-leucine and 3H-L-proline by hepatocytes and cells of the proximal and distal convoluted and of the collecting tubules of the kidney was compared with that of 3H-DL-leucine and 3H-DL-proline in an autoradiographic study. 34 male white Sprague-Dawley rats were killed 1, 2, 6, and 24 hours after the intraperitoneal injection of these amino acids. The rate of incorporation of 3H-L-leucine in the liver and in the renal tubules, as judged by the number of silver grains counted, was about twice that of 3H-L-proline. In the tubules of the kidney the intensity of labelling progressively declined from the proximal convoluted to the collecting tubules. When the two 3H-DL-amino acids were used, almost identical rates of incorporation were found in the liver as well as in the kidney. The only exception was the pars recta of the proximal tubule: Here there could be found an unusually high uptake of 3H-DL-proline. The values were not only higher than those found for the uptake of 3DL-leucine in this particular segment, but they also surpassed those due to 3H-DL-proline and 3DL-leucine in the other parts of the renal tubules, as well as in the liver. The conspicuously high labelling seen in the pars recta after the injection of 3H-DL-proline suggests that there is present in the cells of this segment a d-amino acid oxidase, which may be relatively specific for D-proline. The possibility is considered that this enzyme may participate in a detoxifying function of the pars recta.     

Evaluation of single intratesticular injection of calcium chloride for nonsurgical sterilization of male Black Bengal goats (Capra hircus): a dose-dependent study

This study describes the induction of chemosterilization in three groups each of six adult male Black Bengal goats at 30 days after a single bilateral intratesticular injection of a calcium chloride (CaCl(2), 2H(2)O) solution at the doses of 10, 20 or 40 mg/kg body weight/testis, always in a 2 ml volume of normal saline. Another one group of animals received only 2 ml of normal saline per testis as a control. The induction of chemosterilization was measured using relative testicular weight as well as histomorphological parameters including seminiferous tubular architecture and germ cell association in seminiferous tubules along with morphology of the interstitial space. Biochemical markers included activities of testicular Delta(5), 3beta-hydroxysteroid dehydrogenase (Delta(5), 3beta-HSD), 17beta-hydroxysteroid dehydrogenase (17beta-HSD), catalase, glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) as well as monitoring the level of testicular thiobarbituric acid reactive substances (TBARS), conjugated dienes and reduced glutathione (GSH) content along with plasma concentrations of testosterone, LH and FSH. Histomorphological measures of testes showed total necrosis of testicular tissue at 30 days after an injection of either 20 or 40 mg CaCl(2) along with fibrosis in seminiferous tubules and interstitial spaces. Infiltration of leucocytes was observed with the 40 mg dose. Disintegration of germ cell arrangement in seminiferous tubules and washing out of germ cells from the tubules were noted with the 10mg dose. Relative organ weights, plasma concentrations of testosterone, testicular activities of Delta(5), 3beta-HSD, 17beta-HSD, catalase, GPx, GST, and SOD and testicular contents of GSH all were declined. Increases occurred in testicular TBARS, conjugated dienes and plasma concentrations of LH and FSH with each of the treatments by comparison with the control group. Plasma concentrations of cortisol and fasting blood sugar level as well as packed cell volume (PCV) and total plasma protein were recorded to monitor the changes of chronic stress in the experimental animals. Changes in these parameters were not significant. An intratesticular injection of calcium chloride at specified doses could be a suitable method of sterilization in preference to surgical castration of goats.     

Xenogeneic transplantation of human spermatogonia

In the last 3 years, several studies have shown that xenogeneic transplantation of rodent spermatogonia is feasible. The treatment of infertile patients with spermatogenic arrest using the injection of immature germ cells has yielded only poor results. We attempted to establish a complete spermatogenetic line in the testes of mutant aspermatogenic (W/Wv) and severe combined immunodeficient mice (SCID) transplanted with germ cells from azoospermic men. Spermatogenic cells were obtained from testicular biopsy specimens of men (average age of 34.3 +/- 9 years) undergoing infertility treatment because of obstructive and non-obstructive azoospermia. Testicular tissue was digested with collagenase to promote separation of individual spermatogenic cells. The germ cells were injected into mouse testicular seminiferous tubules using a microneedle (40 microm inner diameter) on a 10 ml syringe. To assess the penetration of the cell suspension into the tubules, trypan blue was used as an indicator. Mice were maintained for 50 to 150 days to allow time for germ cell colonisation and development prior to them being killed. Testes were then fixed for histological examination and approximately 100 cross-sectioned tubules were examined for human spermatogenic cells. A total of 26 testicular cell samples, 16 frozen and 10 fresh, were obtained from 24 men. The origin of the azoospermia was obstructive (OA) in 16 patients and non-obstructive (NOA) in 8 patients. The concentration of spermatogenic cells in the OA group was 6.6 x 10(6) cells/ml, and 1.3 x 10(6) cells/ml in the NOA group (p < 0.01). The different spermatogenic cell types were distributed equally in the OA samples, ranging from spermatogenia to fully developed spermatozoa, but in the NOA group the majority of cells were spermatogonia and spermatocytes. A total of 23 testes from 14 W/Wv mice and 24 testes from 12 SCID mice were injected successfully, as judged by the presence of spermatogenic cells in histological sections of testes removed immediately after the injection. However, sections from the remaining testes examined up to 150 days after injection showed tubules lined with Sertoli cells and xenogeneic germ cells were not found. The reason why the two strains of mouse used as recipients did not allow the implantation of human germ cells is probably due to interspecies specificity involving non-compatible cell adhesion molecules and/or immunological rejection.     

A testis-mediated germline chimera production based on transfer of chicken testicular cells directly into heterologous testes

In this study, we proposed a testis-mediated germline chimera production system based on the transplantation of testicular cells directly into heterologous testes. The testicular cells of juvenile (4-wk-old) or adult (24-wk-old) Korean Ogol chickens with a recessive pigmentation inhibitory gene, with or without prior culture, were injected (2 x 10(7) cells/head) into the seminiferous tubules of juvenile or adult recipients with White Leghorn with a dominant pigmentation inhibitory gene in a 2 x 2 factorial arrangement. The localization of transplanted cells into the inner space of the seminiferous tubules was confirmed within 24 h after injection. Subsequent testcross analyses showed that 7.8% (5/64) of the recipients had chimeric status in their testes. The periods of time from transfer to hatching of the first progeny with black feathers were 38 and 45 days for adult cells transplanted into an adult recipient, 188 days for adult cells into a juvenile recipient, and 137 days for juvenile cells into a juvenile recipient. Culture of the testicular cells derived both colony-forming and monolayer-forming cells. The colony-forming cells were stained positively for periodic acid Schiff solution, and further reacted with anti-SSEA-1, anti-SSEA-3, and anti-SSEA-4 antibodies both before and after culture for 15 days. In conclusion, it may be possible to develop the testis-mediated germline chimera production technique, which extends the feasibility of genetic manipulations in avian species.     

Platinum localization and kidney ultrastructure in the frog after cisplatin administration

X-ray microanalysis was used to study the localization of platinum, sodium and potassium in the frog nephrons 3 days after cisplatin administration (50 mg per kg of body weight). In the frog, like in mammals, platinum is accumulated in the proximal tubules. As evidenced by electron microscopy, the platinum content is correlated with the degree of deterioration of cell ultrastructure. The large scattering of the platinum content of individual tubules (from 0.03 to 0.15%) is probably due to the difference between the initial and late parts of the proximal tubule which is in agreement with the ultrastructural findings.     

Autoradiography after tritiated thymidine labeling of the abortive gametogenesis in hybrid male ducks from the cross male Pekin X female Barbary]

This autoradiographic data concludes that meiotic prophase of the abortive gametogenesis of the sterile hybride drake (from the mating Peking male = Anas platyrhynchos L. X Barbary female = Cairina moschata L.) lasts 5 days 1/4. 6 days after the injection of the marker the seminiferous tubules contain numerous labeles necrosing cells but never typical elongated spermatids.     

小鼠睾丸注射不同转染试剂和注射方法对外源基因表达的影响

为探讨不同转染试剂(LipofectamineTM LTXPLUSTM、Lipofectamine2000和纳米化聚酰胺-胺型树枝状聚合物(PAMAM-D))和睾丸注射方法 (睾丸网注射、曲精细管注射和间质注射)对转基因小鼠生产效率的影响,将pEGFP-C1质粒分别与不同转染试剂混合后,按照不同的注射方法注入小鼠睾丸内,30 d后检测小鼠精子密度、活力、精子阳性率以及配种后仔鼠转基因阳性率。结果 3种转染试剂对小鼠繁殖性能影响由小到大依次为LipofectamineTM LTXPLUSTM、Lipofectamine 2000和PAMAM-D。转染后LipofectamineTM LTXPLUSTM、Lipofectamine 2000和PAMAM-D组精子的GFP阳性率分别为35.65%±0.69%、12.86%±0.35%和10.04%±0.20%。配种后仔鼠的PCR阳性率分别为29.17%、13.70%和5.88%。3种不同注射方法对小鼠睾丸都造成损伤,由小到大依次为睾丸网注射、曲精细管注射和睾丸间质注射,三者的阳性精子比例分别为35.13%±1.727%、15.13%±1.457%和0%,配种后仔鼠的PCR阳性率分别为33.3%、12.5%和0%。结果表明,LipofectamineTM LTXPLUSTM和睾丸网注射对小鼠睾丸的损伤最小,并能获得较高的转染效率。     

Tubular changes in obstructed kidney of adult mice evaluated using immunohistochemistry for segment-specific marker

The main focus of the present investigation is to examine obstructed kidneys due to unilateral ureteral obstruction (UUO) model in adult mice using segment-specific tubular marker and to confirm the detailed morphological evaluation of UUO that is a typical model for the tubulointerstitial fibrosis which is an endpoint outcome of chronic renal diseases. Adult mice were subjected to UUO, and kidneys were harvested 1, 3, 7 days after surgical operation. Expansion of interstitial space both in the cortex and the medulla was confirmed 3 days after UUO by HE- and azan-staining. Interstitial fibrosis developed especially around dilated tubules. Immunohistochemistry for segment-specific antibodies revealed that the proximal tubules and the descending limb of Henle's loop did not dilate until 7 days after UUO, whereas initial dilation of the ascending limb of Henle's loop appeared to occur one day after surgery. The segment from the distal tubules to the collecting ducts began dilating one day after surgery and afterward significantly dilated. The downstream segment of nephron was involved in dilating earlier than the upstream of nephron in obstructed kidney examined in the present study. Moreover, the tubules accompanying apoptosis of tubular epithelia significantly dilated compared with those without apoptotic tubular epithelia. From the above-mentioned findings, we conclude that tubular dilatation of distal segment (from the ascending limb of Henle's loop to the collecting ducts) of nephron develops tubular epithelial apoptosis caused by accumulated urine, which would link to tubular disappearance and its replacement with fibrous tissue in UUO kidney of adult mice.     

Effect of androgens and antiandrogens on the development of the myoid cells of the rat seminiferous tubules (organ culture)

Summary To study the regulation of the development of myoid cells, seminiferous tubules of adult and prepubertal rats were grown in organ culture under the influence of testosterone, HCG and cyproterone acetate. Contractility, EM-structure and histochemical activities of alkaline phosphatase and ATPase of the myoid cells were studied in the adult rat tubules at one week intervals up to 5 weeks in culture, in the prepubertal rat tubules at the age of 15 days and after 15 and 21 days in culture. As in vivo, contractions appear in cultured tubules of prepubertal rats at the age of 15 days. Testosterone and HCG increase the percentage of contractile tubules and the number of filaments of the myoid cells. Cyproterone acetate inhibits both functional and structural development and tends to decrease the enzyme activities. In the cultured adult rat tubules cyproterone acetate causes disappearance of contractility within one week, while contractions normally are found for 3 weeks. Testosterone and HCG have no notable effects on the contractility of adult rat tubules, but they lengthen the persistence of alkaline phosphatase activity. It is concluded that the maturation and also the functioning of the myoid cells are subject to androgenic regulation.     

Palliative effect of curcumin on doxorubicin‐induced testicular damage in male rats

This study aimed to investigate the effect of curcumin (CUR) on doxorubicin (DOX)‐induced testicular damage in male rats. Thirty‐five adult male Wistar rats were used. Control group was received saline for 7 days. CUR group received CUR for 7 days. DOX group received single dose DOX on the 5th day. DOX+ CUR‐100 group received 100 mg/kg/day CUR for 7 days and DOX injection on the 5th day. DOX + CUR‐200 group received 200 mg/kg/day CUR for 7 days and DOX injection on the 5th day. DOX treatment decreased in sperm motility rate, live sperm percentages, cellular antioxidants, and increased malondialdehyde (MDA) levels, necrosis, degenerations, and slimming in seminiferous tubules, and DNA damages in testes by inducing oxidative stress. CUR treatment mitigated significantly these side effects when compared with DOX group in a dose‐dependent manner. In conclusion, CUR treatment can be used in the mitigation of DOX‐induced testicular toxicity.     

Selective destruction and regeneration of rat Leydig cells in vivo

Summary The effect of a single i.p. administration of ethane dimethanesulphonate (EDS) upon rat testicular histology was studied by light microscopy and morphometry up to 4 weeks after treatment. One day after injection the interstitial tissue exhibited degenerating Leydig cells, abundant pyknotic interstitial cells, deposition of cellular debris and extensive networks of fibrillar material. Macrophages contained greatly increased numbers of cytoplasmic inclusion bodies. From 3 to 7 days morphometric analysis showed that Leydig cells and cellular debris had disappeared from the interstitial tissue, leaving only macrophages, fibroblasts and lymphatic endothelial tissue. A very small number of new Leydig cells were seen on day 14, often located in peritubular or perivascular positions. Regeneration of foetal-like Leydig cells occurred by 4 weeks, their cytoplasm containing large lipid inclusions and, numerous Leydig cells were often observed closely applied to the walls of the seminiferous tubules. The observations suggest that, after experimental destruction and depletion of Leydig cells, an interstitial precursor cell, as yet unidentified, gives rise to a new Leydig cell population. EDS thus offers a valuable opportunity to study further the interactions between the seminiferous tubules and the interstitial tissue following the destruction and subsequent regeneration of the Leydig cells.     

Role of testosterone in the early stage of spermatocytogenesis in rats.

The role of testosterone in the early stage of spermatocytogenesis was investigated in newborn rats. The testes of rats, either 0 or 6 days of age, were implanted into those of hypophysectomized adult rats that had or had not been injected with testosterone propionate (TP) after hypophysectomy and also into those in intact adult rats. All the animals were autopsied 17 or 11 days later when the implanted testes reached 17 days of age. The implanted testes were examined for cellular components in the seminiferous tubules. In an additional experiment, newborn rats were injected with TP or cyproterone acetate, an antagonistic substance against androgen, daily for the first 17 days of life and examined for testes. Proliferation of supporting cells and development of seminiferous tubules were less remarkable in the testes of newborn rats which had been implanted into the testes of hypophysectomized rats than in those which had been implanted into the testes of intact adult rats. Proliferation of supporting cells was not stimulated by TP, but development of seminiferous tubules was slightly promoted. Progress in spermatocytogenesis from gonocytes to pachytene primary spermatocytes was observed in the testes of newborn rats which had been implanted into the testes of hypophysectiomized rats. It was not so marked after injection with TP. These results suggested that testosterone might have stimulated development of seminiferous tubules and maturation of spermatocytes in the early stage of spermatocytogenesis by its synergistic action with a gonadotropin, possible follicle-stimulating hormone.     

Immunopathology of murine experimental allergic orchitis

Experimental allergic orchitis (EAO) was induced consistently in BALB/c mice by immunization with homologous testicular tissue homogenate emulsified in complete Freund's adjuvant (CFA) providing that the animals had received simultaneously at least 1 microgram of an extract of Bordetella pertussis rich in pertussigen. All animals thus treated developed orchitis and serum antibody to testicular antigens within 20 days after immunization. The lesions were located in testis (100%), rete testis (37%), cauda epididymis (21%), and vas deferens (37%). Ductus efferentes and caput epididymis were only rarely affected. Early lesions in the seminiferous tubules were characterized by peritubular and/or intratubular accumulation of eosinophils, neutrophils, lymphocytes, and macrophages. This was followed by aspermatogenesis. Late lesions included massive necrosis and extensive fibrosis of the seminiferous tubules. Disruption of blood-testis barrier on day 20 was evidenced by the detection of 1) perfused lanthanum deposits between Sertoli cells and surrounding inflammatory cells inside the seminiferous tubules, 2) deposits of endogenous mouse IgG in germinal epithelium, and 3) probable immune complexes (granular C3) surrounding seminiferous tubules. Murine EAO differed from that of the guinea pig in the lack of involvement of the ductus efferentes, the extensive necrosis, the abundant polymorphonuclear eosinophils in the lesion, and the exquisite requirement of concomitant injection of B. pertussis extract.     

Testicular torsion and its effects on the spermatogenic cycle in the contralateral testis of the rat

The aim of the present study was to evaluate the effects of unilateral testicular torsion on the contralateral testis with respect to the stages of the cycle of the seminiferous epithelium (CSE). Fifty-five male Wistar rats, 60 days old, were used. The animals were divided into 11 groups. Groups 1-5 were subjected to unilateral testicular torsion from 3 to 48 h, followed by detorsion. Groups 6-10 had unilateral orchiectomies after unilateral testicular torsion for 3 to 48 h. Animals constituting group 11 served as the control sham-operated group. All animals were killed after 2 months. The percentage of affected tubules (tubules showing pathological changes) in the contralateral testis was estimated based on the CSE stages. In the torsion/detorsion group, the percentage of affected tubules was significantly greater (58.6%) than in torsion/orchiectomy group (48.0%). Stages VI-XI of the spermatogenic cycle were the most affected when compared with the rest of the stages in each experimental group (P <0.05). These results show that stages VI-XI of the spermatogenic cycle, the stages associated with low antioxidant capacities, are the most sensitive to the effects of testicular torsion on the contralateral testis.     

Transient transmission of a transgene in mouse offspring following in vivo transfection of male germ cells

Sperm-mediated gene transfer in vertebrates has undergone various developments over the last few years, in different laboratories. In the present study, we microinjected a circular plasmid, carrying the lacZ reporter gene mixed with noncommercial cationic lipids, into the seminiferous tubules of anesthetized adult mice. Histochemical analysis was used to estimate the transfection efficiency 48-96 hr and 40 days after injection. As early as 48-96 hr post-injection, an efficient transfection was revealed by a beta-galactosidase expression within both immature and differentiated germ cells. By 40 days post-injection, the specific LacZ expression was restricted to the most immature germ cells in the basal portion of the seminiferous tubules. At this time, some injected males were mated with wild-type females and the progeny were analyzed by PCR and Southern blot. We showed that the transgene was transmitted to the offspring but remained episomal, as it was found in the tail of the young animals but not at adulthood. Therefore, the plasmid seemed to be lost during the numerous germ cells divisions. This plasmid stayed in some tissues, such as skeletal muscle and cardiac muscle. No integrative forms have yet been found with the use of a circular DNA.     

Response of the spermatogenic system to chemical mutagen dipin in SAMP1 senescence-accelerated mice

Specific features of spermatogenesis were studied in senescence-accelerated mice of the strain SAMP1 after one-time injection of the chemical mutagen dipin. Quantitative and histomorphological changes in the spermatogenic epithelium proved to develop gradually. Cell loss and disorganization of spermatogenesis reached the peak as late as on days 28 and 35 after the injection. Differentiating spermatogonia manifested increased sensitivity to dipin. In prophase I of meiosis, developing spermatocytes proved to be less sensitive to the cytotoxic action of dipin at the pachytene than at the preleptotene-leptotene stages. Spermatogenesis in most seminiferous tubules was restored by day 56 after dipin treatment. At the end of the experiment (day 100), both quantitative parameters and morphological pattern of spermatogenesis did not differ significantly from those in the control. Thus, the cytotoxic action of dipin does not lead to irreversible structural disorganization of the spermatogenic epithelium in SAMP1 mice. Radioautography revealed a large proportion of highly differentiated Sertoli cells with ³H-thymidine-labeled nuclei in experimental animals. In some cases, structures resembling embryonic seminiferous tubules were revealed in the vicinity of rete testis in histological sections of testes of experimental mice. These structures contained the cells morphologically similar to gonocytes and immature Sertoli cells.     

All-trans retinoic acid ameliorates inflammatory response mediated by TLR4/NF-κB during initiation of diabetic nephropathy

Diabetic nephropathy (DN) is the leading cause of renal failure worldwide and its complications have become a public health problem. Inflammation, oxidative stress and fibrosis play central roles in the progression of DN that lead to renal failure. Potential deleterious effect of inflammation in early evolution of DN is not fully disclosed. Therefore, it is relevant to explore therapies that might modulate this process in order to reduce DN progression. We explored the beneficial effect of all-trans retinoic acid (ATRA) in early inflammation in glomeruli, proximal and distal tubules in streptozotocin (STZ)-induced diabetes. ATRA was administered (1 mg/kg daily by gavage) on days 3 to 21 after STZ administration. It was found that 21 days after STZ injection, diabetic rats exhibited proteinuria, increased natriuresis and loss of body weight. Besides, diabetes induced an increase in interleukins [IL-1β, IL-1α, IL-16, IL-13, IL-2; tumor necrosis factor alpha (TNF-α)] and transforming growth factor-beta 1 (TGF-β1), chemokines (CCL2, CCL20, CXCL5 and CXCL7), adhesion molecules (ICAM-1 and L-selectin) and growth factors (GM-CSF, VEGF, PDGF) in glomeruli and proximal tubules, whereas ATRA treatment remarkably ameliorated these alterations. To further explore the mechanisms through which ATRA decreased inflammatory response, the NF-κB/p65 signaling mediated by TLR4 was studied. We found that ATRA administration attenuates the TLR4/NF-κB inflammatory signaling and prevents NF-κB nuclear translocation in glomeruli and proximal tubules.