Role of PERK-eIF2α signaling pathway in fetal male rats with hypospadias induced by di-n-butyl phthalate

Endoplasmic reticulum stress induces degradation of glucose transporter proteins during hyperglycemic hepatotoxicity: Role of PERK-eIF2α-ATF4 axis

Hyperglycemia induced reactive oxygen species oxidize macromolecules including cellular proteins leading to their accumulation in Endoplasmic Reticulum (ER) lumen which in turn activates unfolded protein response (UPR) sensors including, PERK (Protein Kinase RNA-Like ER Kinase). Activated PERK induces ER associated degradation of misfolded proteins to lower the ER stress. In the present study, we hypothesized that ER stress leads to the degradation of glucose transporter proteins resulting in complex glucose metabolism. In vivo studies were carried out in the experimental model of hyperglycemia using streptozotocin/nicotinamide induced diabetic male Wistar rats. High glucose (30mM) treated HepG2 cells were used to perform the mechanistic study at different time points. PERK gene knockdown (siRNA transfection) and inhibition by ISRIB (Integrated Stress Response Inhibitor, a potent inhibitor of PERK signaling) confirmed the involvement of PERK axis in regulating the expression and translocation of hepatic glucose transporters. Co-immunoprecipitation and dual immunostaining studies further demonstrated increased degradation of GLUT proteins under high glucose conditions. Moreover, Morin (3,5,7,2',4' pentahydroxyflavone) treatment prevented PERK-eIF2α-ATF4 mediated degradation of glucose transporters and enhanced glucose uptake in both, HepG2 cells and diabetic rats. Targeting aberrant regulation of the expression and translocation of facilitative glucose transporter proteins (GLUT proteins) may provide novel therapeutic strategies for the better management of diabetes.

Autophagy role in environmental pollutants exposure

During the last decades, the potential harmfulness derived from the exposure to environmental pollutants has been largely demonstrated, with associated damages ranging from geno- and cyto-toxicity to tissue malfunction and alterations in organism physiology. Autophagy is an evolutionarily-conserved cellular mechanism essential for cellular homeostasis, which contributes to protect cells from a wide variety of intracellular and extracellular stressors. Due to its pivotal importance, its correct functioning is directly linked to cell, tissue and organismal fitness. Environmental pollutants, particularly industrial compounds, are able to impact autophagic flux, either by increasing it as a protective response, by blocking it, or by switching its protective role toward a pro-cell death mechanism. Thus, the understanding of the effects of chemicals exposure on autophagy has become highly relevant, offering new potential approaches for risk assessment, protection and preventive measures to counteract the detrimental effects of environmental pollutants on human health.

Hypospadias in a Sheltie puppy: A case report

Hypospadias in dogs is a rare pathology in the veterinary practice. The manifestation of hypospadias in dogs is diverse, since there is a varying degree of damage to the urogenital apparatus. The owners of a Sheltie puppy at the age of 3 days came to the clinic due to the difficulty of determining sex, the presence of inflammation of the anus and abdominal skin, defecation and urination violations. Clinical examination of the puppy showed a blind-closed preputial sac, absence of the ventral wall of the prepuce and an open urogenital urine trough was located in its place in the abdominal wall area. On examination of the puppy at the age of 28 days, hyperaemia and swelling of the anus were noted, as well as prolapse of the rectum. Findings of the examination at the age of 4 months consisted of drying of the mucous part of the open urogenital canal chute and accumulation of pus in the underdeveloped preputial sac. Bilateral cryptorchidism and the absence of the scrotum were also found out. A decision on the surgical treatment was made. The anus and the opening of the urethra were separated to form a urethrostomy in the scrotum and restore the integrity of the anus. On the 5th post operative day, oedema and stricture of the reconstructed urethra resulted in difficulty urinating, followed by the formation of urinary fistula in the perineal region below the anus opening. As a result of the chosen surgical treatment approach, the problem with contact dermatitis of the perineum and pollakiuria was solved.