Promising Polyphenols in Parkinson’s Disease Therapeutics

Neurochemical Research - Parkinson’s disease (PD) is a slow progressive, second most common neurodegenerative disease characterized by the loss of dopaminergic neurons from the nigrostriatal...     

Daily variations in plasma melatonin and melatonin receptor (MT1), PER1 and CRY1 expression in suprachiasmatic nuclei of tropical squirrel, Funambulus pennanti

The suprachiasmatic nucleus (SCN) plays a major role in photoperiodic regulation of seasonal functions by modulating the melatonin signal. To date no report exists regarding the role of the ambient photoperiod in the regulation of melatonin receptor MT1 and clock gene (PER1 and CRY1) expression in the SCN of any tropical rodent that experiences the least variation in the photoperiod. We noted the expression of MT1, PER1 and CRY1 in the SCN of a tropical squirrel, Funambulus pennanti, along with the plasma level of melatonin over 24 h during the reproductively active (summer) and inactive (winter) phases. The seasonal day length affected the peripheral melatonin, which was inversely related with the MT1 expression in the SCN. The timing for peak expression of PER1 was the same in both phases, while the decline in PER1 expression was delayed by 4 h during the inactive phase. The CRY1 peak advanced by 4 h during the active phase, while the interval between the peak and decline of CRY1 remained the same in both phases. It can be suggested that seasonally changing melatonin levels modulate MT1 expression dynamics in the SCN, altering its functional state, and gate SCN molecular “clock” gene profiles through changes in PER/CRY expression. Such a regulation is important for photo-physiological adaptation (reproduction/immunity) in seasonal breeders.     

A Proteinase K Inhibitor Using α,β-Unsaturated (Dehydro) Residues: A Presumptive Model

Abstract

Enzymes of the subtilisin family, of which proteinase K is a member, have been studied extensively on account of their numerous biological applications. Specific inhibitors of the proteinases are of immense importance in regulating their activity so as to protect the cells against uncontrolled proteolysis. Using the specific design principles of peptides containing dehydro-Alanine (ΔAla), generated by our theoretical calculations, we present here the design of an inhibitor of proteinase K. Energy minimization and molecular modeling of the interaction of the designed tetrapeptide with the recognition site of proteinase K indicate that it is an effective inhibitor.     

Evidence of salicylic acid pathway with EDS1 and PAD4 proteins by molecular dynamics simulation for grape improvement

Biotic stress is a major cause of heavy loss in grape productivity. In order to develop biotic stress-resistant grape varieties, the key defense genes along with its pathway have to be deciphered. In angiosperm plants, lipase-like protein phytoalexin deficient 4 (PAD4) is well known to be essential for systemic resistance against biotic stress. PAD4 functions together with its interacting partner protein enhanced disease susceptibility 1 (EDS1) to promote salicylic acid (SA)-dependent and SA-independent defense pathway. Existence and structure of key protein of systemic resistance EDS1 and PAD4 are not known in grapes. Before SA pathway studies are taken in grape, molecular evidence of EDS1: PAD4 complex is to be established. To establish this, EDS1 protein sequence was retrieved from NCBI and homologous PAD4 protein was generated using Arabidopsis thaliana as template and conserved domains were confirmed. In this study, computational methods were used to model EDS1 and PAD4 and simulated the interactions of EDS1 and PAD4. Since no structural details of the proteins were available, homology modeling was employed to construct three-dimensional structures. Further, molecular dynamic simulations were performed to study the dynamic behavior of the EDS1 and PAD4. The modeled proteins were validated and subjected to molecular docking analysis. Molecular evidence of stable complex of EDS1:PAD4 in grape supporting SA defense pathway in response to biotic stress is reported in this study. If SA defense pathway genes are explored, then markers of genes involved can play pivotal role in grape variety development especially against biotic stress leading to higher productivity.     

Effect of Sodium-Glucose Cotransport Inhibition on Polycystic Kidney Disease Progression in PCK Rats

The sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA) induces glucosuria and osmotic diuresis via inhibition of renal glucose reabsorption. Since increased diuresis retards the progression of polycystic kidney disease (PKD), we investigated the effect of DAPA in the PCK rat model of PKD. DAPA (10 mg/kg/d) or vehicle was administered by gavage to 6 week old male PCK rats (n=9 per group). Renal function, albuminuria, kidney weight and cyst volume were assessed after 6 weeks of treatment. Treatment with DAPA markedly increased glucose excretion (23.6 ± 4.3 vs 0.3 ± 0.1 mmol/d) and urine output (57.3 ± 6.8 vs 19.3 ± 0.8 ml/d). DAPA-treated PCK rats had higher clearances for creatinine (3.1 ± 0.1 vs 2.6 ± 0.2 ml/min) and BUN (1.7 ± 0.1 vs 1.2 ± 0.1 ml/min) after 3 weeks, and developed a 4-fold increase in albuminuria. Ultrasound imaging and histological analysis revealed a higher cyst volume and a 23% higher total kidney weight after 6 weeks of DAPA treatment. At week 6 the renal cAMP content was similar between DAPA and vehicle, and staining for Ki67 did not reveal an increase in cell proliferation. In conclusion, the inhibition of glucose reabsorption with the SGLT2-specific inhibitor DAPA caused osmotic diuresis, hyperfiltration, albuminuria and an increase in cyst volume in PCK rats. The mechanisms which link glucosuria to hyperfiltration, albuminuria and enhanced cyst volume in PCK rats remain to be elucidated.     

Galectin-3 is associated with prostasomes in human semen

Galectin-3 is a β-galactoside-binding protein involved in immunomodulation, cell interactions, cancer progression, and pathogenesis of infectious organisms. We report the identification and characterization of galectin-3 in human semen. In the male reproductive tract, the ~30 kDa galectin-3 protein was identified in testis, epididymis, vas deferens, prostate, seminal vesicle, and sperm protein extracts. In seminal plasma, galectin-3 was identified in the soluble fraction and in prostasomes, cholesterol-rich, membranous vesicles that are secreted by the prostate and incorporated into seminal plasma during ejaculation. Two-dimensional immunoblot analysis of purified prostasomes identified five galectin-3 isoelectric variants with a pI range of 7.0 to 9.2. Affinity purification and tandem mass spectrometry of β-galactoside-binding proteins from prostasomes confirmed the presence of galectin-3 in prostasomes and identified a truncated galectin-3 variant. The intact galectin-3 molecule contains a carbohydrate recognition domain and a non-lectin domain that interacts with protein and lipid moieties. The identification of a monovalent galectin-3 fragment with conserved carbohydrate-binding activity indicates the functional relevance of this truncation and suggests a regulatory mechanism for galectin-3 in prostasomes. Surface biotinylation studies suggested that galectin-3 and the truncated galectin-3 variant are localized to the prostasome surface. Prostasomes are proposed to function in immunosuppression and regulation of sperm function in the female reproductive tract, are implicated in facilitating sexually-transmitted infections, and are indicated in prostate cancer progression. Given the overlap in functional significance, the identification of galectin-3 in prostasomes lays the groundwork for future studies of galectin-3 and prostasomes in reproduction, disease transmission, and cancer progression.     

Basidiobolomycosis of the Nose and Face: A Case Report and a Mini-Review of Unusual Cases of Basidiobolomycosis

Background  

Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up.     

Construction of genetic linkage map of the medicinal and ornamental plant <Emphasis Type="Italic">Catharanthus roseus</Emphasis>

An integrated genetic linkage map of the medicinal and ornamental plant Catharanthus roseus, based on different types of molecular and morphological markers was constructed, using a F₂ population of 144 plants. The map defines 14 linkage groups (LGs) and consists of 131 marker loci, including 125 molecular DNA markers (76 RAPD, 3 RAPD combinations; 7 ISSR; 2 EST-SSR from Medicago truncatula and 37 other PCR based DNA markers), selected from a total of 472 primers or primer pairs, and six morphological markers (stem pigmentation, leaf lamina pigmentation and shape, leaf petiole and pod size, and petal colour). The total map length is 1131.9 cM (centiMorgans), giving an average map length and distance between two markers equal to 80.9 cM and 8.6 cM, respectively. The morphological markers/genes were found linked with nearest molecular or morphological markers at distances varying from 0.7 to 11.4 cM. Linkage was observed between the morphological markers concerned with lamina shape and petiole size of leaf on LG1 and leaf, stem and petiole pigmentation and pod size on LG8. This is the first genetic linkage map of C. roseus.