Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venom...Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venomous snake commonly found in southeastern China, where it causes a heavy burden of snakebites. To examine the effects of various factors(morphology, sex, age, season, and geographical origin) on the venom yield in this snake, we collected venom samples of 446 individuals(426 adults and 20 neonates) from 10 populations of N. atra over an eightyear period. We used two variables, lyophilized venom mass(venom yield) and solid content of venom(% solids), to quantify the venom yield. We used linear regression analysis to check if venom yield was related to morphological factors, one-way ANOVA and one-way ANCOVA to detect the sexual, ontogenetic, and geographic variation in venom yield, and repeated-measures ANOVA to examine seasonal shifts in venom yield. Our results indicate that venom yield of N. atra is positively related to the morphological traits examined, with male snakes expelling more venom than females. Venom yield in N. atra was age-related, with elder snakes always expelling more venom than younger ones. Geographic variation in venom yield was also observed, while seasonal variation was not. The solid content of venom was lower in males than in females, but this was not related to morphology, season, age, or geography. Our findings suggest that venom yield in N. atra is influenced by multiple factors, as well as by the interactions among these factors.展开更多
Objective To study the protective effects of naja naja atra venom （NNAV） in a rat model of diabetic nephropathy （DN）. Methods The rat diabetes model was induced by intraperitoneal injection of streptozotocin （STZ...Objective To study the protective effects of naja naja atra venom （NNAV） in a rat model of diabetic nephropathy （DN）. Methods The rat diabetes model was induced by intraperitoneal injection of streptozotocin （STZ）. Thirty-two model rats were randomly divided into one DN group （n=8） and three treatment groups （n=8 each） that received NNAV at doses of 30, 90, or 270 I^g/（ks.day） via oral gavage, another eight rats as normal controls. After 12 weeks, all rats were sacrificed and the changes in serum and urine biological index levels were determined by colorimetric assay. Microalbumin （mALB）, N-acetyl-13- glucosaminidase （NAG） and cystatin C （CysC） concentrations were measured by ELISA. Renal tissues were sliced for pathological and immunohistochemical observations. Results Comparied with the DN group, serum glucose was decreased by 31.04%, total cholesterol 21.96%, triglyceride 23.78%, serum creatinine 19.83%, blood urea nitrogen 31.28%, urinary protein excretion 45.42%, mALB 10.42%, NAG 20.65%, CysC 19.57%, whereas albumin increased by 5.55%, high-density lipoprotein-cholesterol 59.09%, creatinine clearance 19.05% in the treatment group by NNAV administration at dose of 90 μg/（kg-day）. NNAV also reduced the levels of malondialdehyde in serum （22.56%） and kidney tissue （9.79%）, and increased superoxide dismutase concentration in serum （15%） and decreased it in renal tissue （8.85%）. In addition, under light microscopy kidney structure was improved and glomerular hypertrophy decreased by 8.29%. As shown by immunohistochemistry, NNAV inhibited transforming growth factorl by 6.70% and nuclear actor-KB by 5.15%.展开更多
基金supported by grants from the National Natural Science Foundation of China (31101635, 31471995 and 31770428)Zhejiang Provincial Foundation of Science (LY14C030007)Open Fund of Jiangsu Key Laboratory for Biodiversity and Biotechnology
文摘Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venomous snake commonly found in southeastern China, where it causes a heavy burden of snakebites. To examine the effects of various factors(morphology, sex, age, season, and geographical origin) on the venom yield in this snake, we collected venom samples of 446 individuals(426 adults and 20 neonates) from 10 populations of N. atra over an eightyear period. We used two variables, lyophilized venom mass(venom yield) and solid content of venom(% solids), to quantify the venom yield. We used linear regression analysis to check if venom yield was related to morphological factors, one-way ANOVA and one-way ANCOVA to detect the sexual, ontogenetic, and geographic variation in venom yield, and repeated-measures ANOVA to examine seasonal shifts in venom yield. Our results indicate that venom yield of N. atra is positively related to the morphological traits examined, with male snakes expelling more venom than females. Venom yield in N. atra was age-related, with elder snakes always expelling more venom than younger ones. Geographic variation in venom yield was also observed, while seasonal variation was not. The solid content of venom was lower in males than in females, but this was not related to morphology, season, age, or geography. Our findings suggest that venom yield in N. atra is influenced by multiple factors, as well as by the interactions among these factors.
基金supported by the Research Project of the Jiangsu Province Key Provincial Talents Program,RC2011112
文摘Objective To study the protective effects of naja naja atra venom （NNAV） in a rat model of diabetic nephropathy （DN）. Methods The rat diabetes model was induced by intraperitoneal injection of streptozotocin （STZ）. Thirty-two model rats were randomly divided into one DN group （n=8） and three treatment groups （n=8 each） that received NNAV at doses of 30, 90, or 270 I^g/（ks.day） via oral gavage, another eight rats as normal controls. After 12 weeks, all rats were sacrificed and the changes in serum and urine biological index levels were determined by colorimetric assay. Microalbumin （mALB）, N-acetyl-13- glucosaminidase （NAG） and cystatin C （CysC） concentrations were measured by ELISA. Renal tissues were sliced for pathological and immunohistochemical observations. Results Comparied with the DN group, serum glucose was decreased by 31.04%, total cholesterol 21.96%, triglyceride 23.78%, serum creatinine 19.83%, blood urea nitrogen 31.28%, urinary protein excretion 45.42%, mALB 10.42%, NAG 20.65%, CysC 19.57%, whereas albumin increased by 5.55%, high-density lipoprotein-cholesterol 59.09%, creatinine clearance 19.05% in the treatment group by NNAV administration at dose of 90 μg/（kg-day）. NNAV also reduced the levels of malondialdehyde in serum （22.56%） and kidney tissue （9.79%）, and increased superoxide dismutase concentration in serum （15%） and decreased it in renal tissue （8.85%）. In addition, under light microscopy kidney structure was improved and glomerular hypertrophy decreased by 8.29%. As shown by immunohistochemistry, NNAV inhibited transforming growth factorl by 6.70% and nuclear actor-KB by 5.15%.
