Psidium guajava Linn leaf ethanolic extract: In vivo giardicidal potential with ultrastructural damage,anti-inflammatory and antioxidant effects

Introduction and aimConsidering the magnitude of giardiasis problem, the side-effects of the used anti-giardia drugs and the resistance posed against them, the current study aimed to evaluate the in-vivo giardicidal effect of Psidium guajava leaf extract (PGLE).MethodsFor fulfilling this aim, five Swiss-albino mice groups were included; GI: non-infected, GII: Giardia-infected and non-treated, GIII: Giardia-infected and metronidazole-treated, GIV: Giardia-infected and PGLE-treated, and GV: Giardia-infected and treated with both metronidazole and PGLE. Treatment efficacy was assessed via; Giardia cyst viability and trophozoite count, trophozoite electron microscopic ultrastructure, duodenal histopathological scoring, immunohistochemistry for TNF-α and duodenal scanning electron microscopy. Moreover, mice serum liver enzymes, total bilirubin, albumin, lipid profile including; total cholesterol, HDL, LDL and triglycerides were assessed. Additionally, hepatic oxidative stress markers including; malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH) and superoxide dismutase (SOD) were measured.ResultsResults showed that PGLE whether alone or combined with metronidazole has induced significant trophozoite count reduction and major architectural changes. Duodenal histological improvement, and local protective anti-inflammatory effect were confirmed. PGLE has also helped in healing of Giardia-induced gut atrophy. Thus, offered a comprehensive therapy for both the pathogen and the resultant pathological sequalae. Serum markers showed favorable hepatoprotective effect. Total cholesterol, LDL and triglycerides levels were less in PGLE-treated group than in metronidazole-treated group. Hepatic oxidative stress markers revealed the promising extract antioxidant effect. This study highlights, the promising in-vivo giardicidal PGLE activity, that was comparable to metronidazole, thus, the extract would be an ideal strongly recommended treatment for giardiasis. When combined with metronidazole, the extract potentiated its therapeutic effect. Besides, having hepatoprotective, anti-inflammatory, and antioxidant properties, the extract can combat the major side effects of metronidazole therapy.     

Impact of the age of Biomphalaria alexandrina snails on Schistosoma mansoni transmission: modulation of the genetic outcome and the internal defence system of the snail

Of the approximately 34 identified Biomphalariaspecies,Biomphalaria alexandrina represents theintermediate host of Schistosoma mansoni in Egypt. Usingparasitological and SOD1 enzyme assay, this study aimed to elucidate the impact ofthe age of B. alexandrina snails on their genetic variability andinternal defence against S. mansoni infection. Susceptible andresistant snails were reared individually for self-reproduction; four subgroups oftheir progeny were used in experiment. The young susceptible subgroup showed thehighest infection rate, the shortest pre-patent period, the highest total cercarialproduction, the highest mortality rate and the lowest SOD1 activity. Among the youngand adult susceptible subgroups, 8% and 26% were found to be resistant, indicatingthe inheritance of resistance alleles from parents. The adult resistant subgroup,however, contained only resistant snails and showed the highest enzyme activity. Thecomplex interaction between snail age, genetic background and internal defenceresulted in great variability in compatibility patterns, with the highest significantdifference between young susceptible and adult resistant snails. The resultsdemonstrate that resistance alleles function to a greater degree in adults, withhigher SOD1 activity and provide potential implications for Biomphalariacontrol. The identification of the most susceptible snail age enablesdetermination of the best timing for applying molluscicides. Moreover, adultresistant snails could be beneficial in biological snail control.     

Stress degradation studies on betahistine and development of a validated stability-indicating assay method

The purpose of this work was to study the stability of betahistine (BET) at different stress conditions and to develop a sensitive stability-indicating high-performance liquid chromatographic (HPLC) assay method. The stress conditions applied were including the effect of heat, moisture, acid-base, and ultra-violet (UV) light. Betahistine and its decomposition products were derivatized by reaction with dansyl chloride (Dan-Cl) and analyzed by HPLC equipped with fluorescence detector (FL) set at 336 and 531 nm as excitation and emission wavelengths, respectively. The drug was particularly labile at UV light and oxygen rich media. Two potential degradation products could be separated and identified by spectral methods. The chromatographic method involved Zorbax Eclipse XDB-C(18) column kept at 30+/-2 degrees C and a gradient elution with mobile phase composed of acetonitrile and 0.02 mol L(-1) sodium acetate. The response factor of dansylated BET monitored by fluorescence detection was 32 times more than its UV response. The calibration curve of BET in bulk form was linear from 0.005 to 4.2 ng microL(-1). Intraday and interday precision were less than 0.04% (CV), and accuracy was between 99.2% and 100.9% over 2.0 ng microL(-1). The limit of detection was 0.002 ng microL(-1). The method was also validated for sample stability during reaction, robustness and selectivity. The method was applied for purity testing of betahistine in tablet form.     

Physiological aspects of tolerance in <Emphasis Type=Italic>Atriplex</Emphasis><Emphasis Type=Italic>halimus</Emphasis> L. to NaCl and drought

Forty-day-old seedlings of Atriplex halimus were treated either with NaCl (50, 300 and 550 mM) for the subsequent 30 days or with 15% PEG for the subsequent 10 days. As much as 50 mM of NaCl significantly increased shoot fresh and dry weight and height; nevertheless, 300 or 550 mM NaCl seemed to have no effect. On the other hand, these growth parameters were not affected by drought after 3 or 6 days, but were reduced after 10 days. The gas exchange parameters (photosynthetic rate, stomatal conductance and transpiration rate) were increased by 50 mM NaCl, but decreased by 300 and 550 mM. These parameters were decreased in response to drought only after 10 days of withholding water. In contrast to Na⁺, K⁺ was significantly decreased by NaCl but not by drought. The time course effect revealed that phosphoenol pyruvate carboxylase (PEPC) protein was doubled in response to NaCl after 1 and 5 h and continued thereafter, higher than control, while drought had no significant effect. Rubisco seemed unchanged by NaCl or drought. It could be concluded that the decrease in fresh weight might be attributed to the decrease in water content. Moreover, the decrease in photosynthesis could result from a decrease in stomatal conductance, a protective mechanism against water loss to improve water use efficiency. These findings indicate that Atriplex halimus tolerates NaCl and drought through decreasing growth, reducing gas exchange parameters to improve water use efficiency, uptake Na⁺ and saving, if any, the photosynthetic enzyme particularly PEPC.     

Value of the cell cycle arrest biomarkers in the diagnosis of pregnancy-related acute kidney injury

Background: Pregnancy-related acute kidney injury (PRAKI) is still a common serious problem in developing countries. Insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor metalloproteinases-2 (TIMP-2) can identify critically ill patients at risk for the development of severe AKI. Aim: To identify main causes and timing of PRAKI and to study the G1 cell cycle arrest biomarkers in cases diagnosed with (PRAKI) as a diagnostic tool. Methods: 80 pregnant women diagnosed with PRAKI were recruited from a single hospital as well as 30 age-matched pregnant women with normal pregnancy participated in the present study. A urine specimen was collected from all study participants with established AKI within 24 h of ICU admission to measure [TIMP-2]*[IGFBP7]. Results: The incidence of PRAKI was 1.1%. The most common cause of PRAKI is pre-eclampsia/eclampsia spectrum (61%). Most of the cases occur in the third trimester (60%) and postpartum period (23%). At a cutoff 0.33 ng/ml, the estimated sensitivity and specificity of urinary [TIMP-2]*[IGFBP7] in predicting PRAKI is 100% (95% CI) with NPV and PPV are 100%. Conclusion: Urinary [TIMP-2]*[IGFBP7] serves as a sensitive and specific biomarker in the diagnosis of PRAKI.     

Allelopathic effect of Nymphaea lotus L. on growth and yield of cultivated rice around Lake Manzala (Nile Delta)

Lotus infestation of ricefields is a major cause of crop failure and decrease of grain yield in the newly reclaimed cut-off areas around lake Manzala, Egypt. This study provides insights in the allelopathic effect of Nymphaea lotus L. on rice (Oryza sativa cavr. Giza-177). Lotus rhizome extracts were inhibitory to seed germination and seedling growth of rice. The degree of inhibition was dependent on extract type and concentration. Ethanol and water extracts were more inhibitory than chloroform extracts. The phenolic fraction of ethanol extracts showed the highest inhibitory effects. In a target (rice)-neighbour (lotus) pot experiment, rice dry mass and relative growth rate were dependent on its age and on lotus rhizome density, with decreased growth at increased lotus density. Field data on infested and non-infested ricefields demonstrated a decreased leaf area index and yield in infested fields. Identification of the potential allelochemical compounds by gas chromatography/mass spectrometry revealed the presence of allelopathic phenolics in lotus rhizomes.     

Protective effect of mirtazapine and hesperidin on cyclophosphamide-induced oxidative damage and infertility in rat ovaries

Cyclophosphamide (CP) causes infertility due to ovarian toxicity. The toxicity mechanism suggests oxidative stress. We assessed whether mirtazapine (MTZ) and hesperidin (HSP) could promote ovarian protection against damage due to CP chemotherapy. Female Wistar rats aged 14 weeks were used. Animals were divided into four groups: control vehicle group (n = 8); CP group (n = 8, rats received 150 mg/kg of CP, single intraperitoneal [i.p.] injection); CP + MTZ group (n = 8, rats received same dose of CP + 30 mg/kg of MTZ, orally, daily); and HSP + CP group (n = 8, rats received same dose of CP + 100 mg/kg of HSP, orally, daily). After eight days of medication, ovaries were removed and ovarian toxicity was assessed by counting follicles and corpora lutea. Nitric oxide (NO) and malondialdehyde (MDA) levels, myeloperoxidase (MPO), glutathione peroxidase (GPx), and superoxide dismutase (SOD) activities were estimated in ovarian tissue. NO level, MDA level, and MPO activity were increased (P < 0.001), while, GPx and SOD activities were lowered significantly (P < 0.001) in CP-treated group compared with control vehicle. In addition, ovulation, number of follicles, and ovarian weight were reduced by CP treatment. On the contrary, rats pretreated with MTZ and HSP showed significant decrease in NO, MDA levels, and MPO activity, while, activities of SOD and GPx were increased (P < 0.001). Oxidative stress induced by CP in the rat ovary causes infertility in the female rats. HSP and MTZ could reverse this effect and provide protection of fertility against CP-induced toxicity.     

A note on the vegetation on islands in Lake Manzala,Egypt

Lake Manzala is one of the Deltaic Mediterranean lakes in Egypt. It comprises over 1000 islands of various sizes, the vegetation of which is halophytic. Seven community types are described, dominated by: Phragmites australis, Juncus acutus, J. rigidus, Arthrocnemum macrostachyum, Atriplex portulacoides, Halocnemum strobilaceum and Zygophyllum aegyptium. Each of these communities has been analysed and its habitat described and discussed.     

Proline induces the expression of salt-stress-responsive proteins and may improve the adaptation of Pancratium maritimum L. to salt-stress

Proline is an important component of salt-stress responses of plants. In this study the role of proline as part of salt-stress signalling in the desert plant Pancratium maritimum L. was examined. The data showed that salt-stress brought about a reduction of the growth and protein content, particularly at 300 mM NaCl, that was significantly increased by exogenous proline. In the leaves, salt-stress up-regulated ubiquitin, a small protein targeting damaged proteins for degradation via the proteasome, up to 5-fold as detected by western blotting. This change was also affected by proline even in non-stressed leaves. However, salt-stress resulted in a decrease in the amount of ubiquitin-conjugates, particularly in the roots, and this effect was reversed by exogenous proline. Severe salt-stress resulted in an inhibition of the antioxidative enzymes catalase and peroxidase as revealed by spectrophotometric assays and activity gels, but the activity of these enzymes was also maintained significantly higher in the presence of proline. Salt-stress also up-regulated several dehydrin proteins, analysed by western blotting, even in non-stressed plants. It is concluded that proline improves the salt-tolerance of Pancratium maritimum L. by protecting the protein turnover machinery against stress-damage and up-regulating stress protective proteins.     

Vasoactive intestinal peptide induces proliferation of human hepatocytes

Objectives

Proliferation of hepatocytes in vitro can be stimulated by growth factors such as epidermal growth factor (EGF), but the role of vasoactive intestinal peptide (VIP) remains unclear. We have investigated the effect of VIP on maintenance and proliferation of human hepatocytes.

Materials and methods

Human hepatocytes were isolated from liver specimens obtained from patients undergoing liver surgery. Treatment with VIP or EGF was started 24 h after plating and continued for 3 or 5 d. DNA replication was investigated by Bromodeoxyuridine (BrdU) incorporation and cell viability detected by MTT assay. Cell lysate was analysed by western blotting and RT‐PCR. Urea and albumin secretion into the culture supernatants were measured.

Results

VIP increased DNA replication in hepatocytes in a dose‐dependant manner, with a peak response at day 3 of treatment. VIP treatment was associated with an increase in mRNA expression of antigen identified by monoclonal antibody Ki‐67 (MKI‐67) and Histone Cluster 3 (H3) genes. Western blotting analysis showed that VIP can induce a PKA/B‐Raf dependant phosphorylation of extracellular signal‐regulated kinases (ERK). Although EGF can maintain hepatocyte functions up to day 5, no marked efffect was found with VIP.

Conclusions

VIP induces proliferation of human hepatocytes with little or no effect on hepatocyte differentiation. Further investigation of the role of VIP is required to determine if it may ultimately support therapeutic approaches of liver disease.