Resveratrol ameliorates diabetes-induced renal damage through regulating the expression of TGF-beta 1, collagen IV and Th17/Treg-related cytokines in rats / El resveratrol mejora el daño renal inducido por la diabetes a través de la regulación de la expresión de TGF-beta 1, colágeno IV y las citocinas relacionados con Th17/Treg en ratas

OBJECTIVES: This study aimed at detecting the protective effects of resveratrol on diabetes-induced renal damage and on the expression of transforming growth factor-beta 1 (TGF-β1), collagen IV and Th17/Tregrelated cytokines in streptozotocin-induced diabetic rats. METHODS: Twenty diabetic rats were further randomly divided into diabetic model group (DM group) and resveratrol group with 10 animals in each group. Another 10 non-diabetic rats served as control. The dia-betic rats in the resveratrol group were administered resveratrol for eight consecutive weeks (via gavage, 50 mg/kg daily, dissolved in saline). Rats in the control group and DM group received the same volume of saline only (via gavage). Renal function was measured. Histopathology changes of the kidney tissue were observed using haematoxylin and eosin staining. Levels of TGF-β1 and collagen IV in kidney homogenate were measured with enzyme-linked immunosorbent assay (ELISA). The level of Th17-related cytokines (IL-17A, IL-25) and Treg-related cytokines (IL-35, IL-10) in serum and in the supernatant of the kidney homogenate were determined using ELISA. RESULTS: Diabetic rats had damaged renal function, higher levels of TGF-β1, collagen IV, IL-17A and IL-25, as well as lower levels of IL-35 and IL-10, when compared to the control rats. Compared to the diabeticrats without resveratrol treatment, application of resveratrol to the diabetic rats ameliorated the renal function, inhibited the expression of TGF-β1, collagen IV, IL-17A and IL-25, and increased the expression IL-35 and IL-10. CONCLUSION: Resveratrol might ameliorate diabetes-induced renal damage through mediating the balance of Th17/Treg-related cytokines and inhibiting the expression of TGF-β1 and collagen IV.

OBJETIVOS: Este estudio estuvo encaminado a detectar los efectos protectores del resveratrol en el daño renal inducido por diabetes y en la expresión del factor de crecimiento transformante beta-1 (TGF-β1), el colágeno IV, y las citocinas relacionados con Th17/Treg en ratas con diabetes inducida por estreptozotocina. MÉTODOS: Veinte ratas diabéticas fueron divididas aleatoriamente en un grupo modelo diabético (Grupo MD) y un grupo de resveratrol, con 10 animales en cada grupo. A las ratas diabéticas en el grupo de resveratrol se les administró resveratrol durante ocho semanas consecutivas (mediante sonda nasogástrica, 50 mg/kg diarios, disuelto en suero salino). Las ratas en el grupo control y el grupo MD recibieron el mismo volumen de solución salina solamente (vía sonda nasogástrica). Se midió la función renal. Se observaron cambios en la histopatología del tejido del riñón usando tinción con hematoxilina y eo-sina. Se midieron los niveles de TGF-β1 y colágeno IV en un homogeneizado de riñón con ensayo por inmunoabsorción ligado a enzimas (ELISA). El nivel de las citocinas de Th17 (IL-17A, IL-25) y las citocinas de Treg (IL-35, IL-10) en suero y en el sobrenadante del homogeneizado de riñón, se determinaron mediante ELISA. RESULTADOS: Las ratas diabéticas tuvieron daño de la función renal, niveles más altos de TGF-β1, colágeno IV, IL-17A y IL-25, así como niveles más bajos de IL-35 e IL-10, en comparación con las ratas control. En comparación con las ratas diabéticas sin tratamiento con resveratrol, la aplicación de resveratrol en las ratas diabéticas mejoró la función renal, inhibió la expresión de TGF-β1, colágeno IV, IL-17A y IL-25 y aumentó la expresión de IL-35 y IL-10. CONCLUSIÓN: El resveratrol podría mitigar el daño renal inducido por la diabetes mediante la mediación con el equilibrio de las citocinas relacionados con Th17/Treg, e inhibiendo la expresión de TGF-β1 y colágeno IV.

Maternal nicotine induces collagen type IV changes in the mice lung parenchyma and its vessels

One of the undesirable effects of maternal nicotine exposure during pregnancy is pulmonary hypertension. Since nicotine binds to its receptors on pulmonary vessels the hypothesis of this research was the possible structural changes that nicotine may cause on newborn vessels. Twenty-four female BALB/c mice were mated and finding vaginal plug was assumed as day zero of pregnancy. Pregnant mice were divided into 2 experimental and 2 control groups. Experimental group 1 received 3 mg/kg nicotine intraperitoneally from day 5 of gestation until the last day of pregnancy. Experimental group 2 received the same amount of nicotine during the same gestational days as well as the first 2 weeks after birth [lactation]. The control groups received the same volume of normal saline during the same periods. At the end of exposure times, all the newborns [experimental and control] were anesthetized, their lungs were removed and immunohistochemical studies were carried out for tracing collagen. Our findings indicated that collagen reaction in the bronchial basement membrane [BBM] and extracellular matrix [ECM] of the lung parenchyma in experimental groups increased significantly compared to the control groups but these changes were not observed in BM of lung vessels in the experimental groups. These data indicate that nicotine exposure during pregnancy does not cause a significant change in collagen type IV in BM of lung vessels. But this does not mean that other types of collagen fibers do not indicate change because the wall thickness of pulmonary vessels in experimental groups increased significantly compared to the control groups

Sec61alpha synthesis is enhanced during translocation of nascent chains of collagen type IV in F9 teratocarcinoma cells after retinoic acid treatment

Nascent procollagen peptides and other secretory proteins are transported across the endoplasmic reticulum (ER) membrane through a protein-conducting channel called translocon. Sec61alpha, a multispanning membrane translocon protein, has been implicated as being essential for translocation of polypeptide chains into the cisterns of the ER. Sec61alpha forms a protein complex with collagen and Hsp47, an ER-resident heat shock protein that binds specifically to collagen. However, it is not known whether Sec61alpha is ubiquitously produced in collagen-producing F9 teratocarcinoma cells or under heat shock treatment. Furthermore, the production and utilization of Sec61alpha may depend on the stage of cell differentiation. Cultured F9 teratocarcinoma cells are capable of differentiation in response to low concentrations of retinoic acid. This differentiation results in loss of tumorigenicity. Mouse F9 cells were grown in culture medium at 37ºC and 43ºC (heat shock treatment) treated or not with retinoic acid, and labeled in certain instances with 35S-methionine. Membrane-bound polysomes of procollagen IV were then isolated. Immunoprecipitation and Western blot analysis were performed using polyclonal antibodies against collagen IV, Hsp47 and Sec61alpha. Under retinoic acid-untreated conditions, F9 cells produced undetectable amounts of Sec61alpha. Sec61alpha, Hsp47 and type IV collagen levels were increased after retinoic acid treatment. Heat shock treatment did not alter Sec61alpha levels, suggesting that Sec61alpha production is probably not affected by heat shock. These data indicate that the enhanced production of Sec61alpha in retinoic acid-induced F9 teratocarcinoma cells parallels the increased synthesis of Hsp47 and collagen type IV