scholarly journals Study on the Optimization and Stability of Single-dose Streptozotocin-induced Diabetic Modelling in Rats

Author(s):  
Yao Zhang ◽  
Jiao Zhang ◽  
Ming Hong ◽  
Jingyi Huang ◽  
Rui Wang ◽  
...  

Abstract Aim: This study was performed to optimize the experimental conditions in streptozotocin (STZ)-induced diabetic model by using Sprague-Dawley (SD) rats to evaluate the stability of the model.Methods: In addition to the control group, the male and female SD rats were randomly divided into the following treatment groups (with six rats per group): STZ 45 (45 mg/kg STZ); STZ 65 (65 mg/kg STZ); STZ 85 (85 mg/kg STZ); high-fat diet with STZ 45; high-fat diet with STZ 65; and high-fat diet with STZ 85. Changes in the body weight and blood glucose were observed dynamically. Results: No significant differences were found in the blood glucose or body weight between the STZ 45 and control groups in both male and female rats, whether or not the rats were on a high-fat diet. However, significant differences were found in the blood glucose between the high-dose STZ and control groups in both male and female rats, regardless of whether the rats were on a high-fat diet or not (P<0.05 or P<0.01). Compared with the control group, significant differences in the blood glucose levels (P<0.05 or P<0.01) and higher blood glucose levels were found in the male rats fed with normal diet than those of rats fed with high-fat diet.Conclusions: In this study, male rats fed with ordinary feed and injected with 65 mg/kg STZ were the most stable and ideal diabetic rats.

2020 ◽  
Author(s):  
Yao Zhang ◽  
jiao Zhang ◽  
Ming Hong ◽  
Jingyi Huang ◽  
Rui Wang ◽  
...  

Abstract BackgroundOptimization of experimental conditions in streptozotocin induced diabetic model in Sprague Dawley (SD) rats to evaluate the stability of the model.MethodsMale and female SD rats were randomly divided into control group, STZ 45 group (STZ: 45 mg / kg), STZ 65 group (STZ: 65 mg / kg), STZ 85 group (STZ: 85 mg / kg), high fat diet with STZ 45 group (STZ: 45 mg / kg), high fat diet with STZ 65 group (STZ: 65 mg / kg), high fat diet with STZ 85 group (STZ: 85 mg / kg). N = 6 in each group. The changes of body weight and blood glucose were observed dynamically.ResultsThere was no significant difference in blood glucose or body weight between the STZ 45 group and the control group in both male and female rats, whether or not they were on a high-fat diet. However, there were significant differences in blood glucose between the high-dose STZ group and the control group in both male and female rats, regardless of whether the rats were on a high-fat diet or not (P < 0.05 or P < 0.01). Compared with the control group, there were significant differences in blood glucose levels (P < 0.05 or P < 0.01) and higher blood glucose levels in the male rats fed with the normal diet than that in those fed with the high-fat diet.ConclusionsIn this study, male rats fed with ordinary feed and injected STZ dose of 65 mg / kg were the most stable and ideal diabetic rat.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A537-A537
Author(s):  
Shiori Minabe ◽  
Kinuyo Iwata ◽  
Hitoshi Ozawa

Abstract Metabolic stress resulting from a nutrient excess causes infertility in both sexes. Kisspeptin-neurokinin B-dynorphin (KNDy) neurons in the arcuate nucleus (ARC) have been suggested to be key players in reproduction via direct stimulation of gonadotropin-releasing hormone (GnRH) and subsequent gonadotropin release in mammalian species. In this study, we investigated the sex differences in the effects of a high-fat diet (HFD) on KNDy-associated gene expression in the ARC to determine the pathogenic mechanism underlying obesity-induced infertility. Wistar-Imamichi strain male and female rats (7 weeks of age) were fed either a standard diet (10% calories from fat) or high-fat diet (45% calories from fat) for 4 months. In male rats, the HFD caused a significant suppression of Kiss1(encoding kisspeptin), Tac3(encoding neurokinin B), and Pdyn(encoding dynorphin A) gene expression in the ARC, resulting in a decrease in plasma luteinizing hormone (LH) levels. In female rats, 58% of the HFD-fed female rats exhibited irregular estrous cycles, while the other rats showed regular cycles. LH pulses were found, and the numbers of ARC Kiss1-,Tac3-, and Pdyn-expressing cells were high in control animals and almost allHFD-fed female rats, but two out of 10 rats showed profound HFD-induced suppression of LH pulse frequency and reduction in these cells. No statistical differences in LH secretion or ARC KNDy gene expression were observed between HFD-fed and control female rats. Additionally, the number of Gnrh1-expressing cells in the preoptic area was comparable between the groups in both sexes. Our findings revealed that HFD-fed male rats showed KNDy-dependent infertility, while irregular menstruation was mainly induced by KNDy-independent pathways during the incipient stage of obese infertility in female rats. Taken together, hypothalamic kisspeptin neurons in male rats may be susceptible to HFD-induced obesity compared with those in female rats.


2017 ◽  
Vol 24 (02) ◽  
pp. 216-220
Author(s):  
Faizania Shabbir ◽  
M. Mazhar Hussain ◽  
Tausif Ahmed Rajput ◽  
Alamgir Khan

Objectives: To observe the effect of obesity and subsequent atorvastatinadministration on MPV in high fat diet induced obese male and female Sprague Dawley rats.Study Design: Randomized control trial (RCT). Setting: Department of Physiology, Army MedicalCollege, Rawalpindi. Animal procurement and blood sampling was done at National Instituteof Health (NIH), Islamabad and biochemical assays were performed at Centre for Research inExperimental and Applied Medicine (CREAM), Army Medical College, Rawalpindi. Period: Thestudy was completed in 12 months. Material and Methods: Ninety healthy Sprague Dawley(male and female) rats were purchased and divided randomly into three equal groups. Ratsin normal control group (Group I) were given normal chow diet for three weeks. Rats in obesecontrol group (Group II) were given high fat diet for three weeks. Rats in obese treated group(Group III) were administered atorvastatin for three weeks in a dose of 10 mg/kg/day orally bygavage method after obesity induction. Terminal sampling was done at the end of the studyby intra-cardiac puncture. MPV is a part of blood complete picture that was analysed by KX 21Sysmex Hematology Analyzer. Results: High fat diet induced obesity resulted in a significant(p < 0.05) increase in MPV. The MPV was significantly (p < 0.05) decreased after atorvastatinadministration. The result was comparable for both genders. Conclusions: Obesity increasesMPV and hence the risk of adverse cardiovascular outcome. Atorvastatin apart from its knownlipid lowering effect, decreases MPV and can play a beneficial role in decreasing cardiovascularmorbidity and mortality. 


1973 ◽  
Vol 74 (1) ◽  
pp. 88-104 ◽  
Author(s):  
T. Jolín ◽  
M. J. Tarin ◽  
M. D. Garcia

ABSTRACT Male and female rats of varying ages were placad on a low iodine diet (LID) plus KClO4 or 6-propyl-2-thiouracil (PTU) or on the same diet supplemented with I (control rats). Goitrogenesis was also induced with LID plus PTU in gonadectomized animals of both sexes. The weight of the control and goitrogen treated animals, and the weight and iodine content of their thyroids were determined, as well as the plasma PBI, TSH, insulin and glucose levels. The pituitary GH-like protein content was assessed by disc electrophoresis on polyacrylamide gels. If goitrogenesis was induced in young rats of both sexes starting with rats of the same age, body weight (B.W.) and pituitary growth hormone (GH) content, it was found that both the males and females developed goitres of the same size. On the contrary, when goitrogenesis was induced in adult animals, it was found that male rats, that had larger B.W. and pituitary GH content than age-paired females, developed larger goitres. However, both male and female rats were in a hypothyroid condition of comparable degree as judged by the thyroidal iodine content and the plasma PBI and TSH levels. When all the data on the PTU or KClO4-treated male and female rats of varying age and B.W. were considered together, it was observed that the weights of the thyroids increased proportionally to B.W. However, a difference in the slope of the regression of the thyroid weight over B.W. was found between male and female rats, due to the fact that adult male rats develop larger goitres than female animals. In addition, in the male rats treated with PTU, gonadectomy decreased the B.W., pituitary content of GH-like protein and, concomitantly, the size of the goitre decreased; an opposite effect was induced by ovariectomy on the female animals. However, when goitrogenesis was induced in weight-paired adult rats of both sexes, the male animals still developed larger goitres than the females. Among all the parameters studied here, the only ones which appeared to bear a consistent relationship with the size of the goitres in rats of different sexes, treated with a given goitrogen, were the rate of body growth and the amount of a pituitary GH-like protein found before the onset of the goitrogen treatment. Moreover, though the pituitary content of the GH-like protein decreased as a consequence of goitrogen treatment, it was still somewhat higher in male that in female animals. The present results suggest that GH may somehow be involved in the mechanism by which male and female rats on goitrogens develop goitres of different sizes, despite equally high plasma TSH levels.


2018 ◽  
Vol 315 (6) ◽  
pp. H1713-H1723 ◽  
Author(s):  
Lia E. Taylor ◽  
Ellen E. Gillis ◽  
Jacqueline B. Musall ◽  
Babak Baban ◽  
Jennifer C. Sullivan

Evidence supports a sex difference in the impact of a high-fat diet (HFD) on cardiovascular outcomes, with male experimental animals exhibiting greater increases in blood pressure (BP) than female experimental animals. The immune system has been implicated in HFD-induced increases in BP, and there is a sex difference in T-cell activation in hypertension. The goal of this study was to determine the impact of HFD on BP and aortic and renal T cell profiles in male and female Dahl salt-sensitive (DSS) rats. We hypothesized that male DSS rats would have greater increases in BP and T cell infiltration in response to a HFD compared with female DSS rats. BP was measured by tail-cuff plethysmography, and aortic and renal T cells were assessed by flow cytometric analysis in male and female DSS rats on a normal-fat diet (NFD) or HFD from 12 to 16 wk of age. Four weeks of HFD increased BP in male and female DSS rats to a similar degree. Increases in BP were accompanied by increased percentages of CD4+ T cells and T helper (Th)17 cells in both sexes, although male rats had more proinflammatory T cells. Percentages of renal CD3+ and CD4+ T cells as well as Th17 cells were increased in both sexes by the HFD, although the increase in CD3+ T cells was greater in male rats. HFD also decreased the percentage of aortic and renal regulatory T cells in both sexes, although female rats maintained more regulatory T cells than male rats regardless of diet. In conclusion, both male and female DSS rats exhibit BP sensitivity to a HFD; however, the mechanisms mediating HFD-induced increases in BP may be distinct as male rats exhibit greater increases in the percentage of proinflammatory T cells than female rats. NEW & NOTEWORTHY Our study demonstrates that male and female Dahl salt-sensitive rats exhibit similar increases in blood pressure to a high-fat diet and an increase in aortic and renal T cells. These results are in contrast to studies showing that female rats remain normotensive and/or upregulate regulatory T cells in response to hypertensive stimuli compared with male rats. Our data suggest that a 4-wk high-fat diet has sex-specific effects on the T cell profile in Dahl salt-sensitive rats.


2010 ◽  
Vol 26 (3) ◽  
pp. 291-302 ◽  
Author(s):  
Antònia Nadal-Casellas ◽  
Emilia Amengual-Cladera ◽  
Ana María Proenza ◽  
Isabel Lladó ◽  
Magdalena Gianotti

2020 ◽  
Vol 374 (1) ◽  
pp. 6-15
Author(s):  
Jeremiah Ramos ◽  
Ethan J. Hardin ◽  
Alice H. Grant ◽  
Grace Flores-Robles ◽  
Adrian T. Gonzalez ◽  
...  

2010 ◽  
Vol 88 (7) ◽  
pp. 753-759 ◽  
Author(s):  
Asdghig H. Der-Boghossian ◽  
Sara R. Saad ◽  
Claudine Perreault ◽  
Chantale Provost ◽  
Danielle Jacques ◽  
...  

The aim of this study was to determine whether the jejunal oligopeptide transporter PepT1 is regulated by insulin and whether this regulation is sex-dependent in type 1 diabetic rats. PepT1 expression, real-time polymerase chain reaction, and Western blots were performed using jejunal segments from 4 groups of male and female rats: normal (nondiabetic), insulin-treated nondiabetic, streptozotocin (STZ)-induced diabetic (type 1 diabetes), and insulin-treated diabetic models. Furthermore, the same segments from all groups underwent perfusion to assess uptake of the dipeptide glycylsarcosine through PepT1. Our results showed that insulin treatment of nondiabetic female rats decreased blood glucose level but did not affect nondiabetic male rats. In both male and female diabetic rats, insulin did not completely decrease blood glucose level. Insulin treatment decreased PepT1 mRNA level in nondiabetic male rats and increased mRNA level in nondiabetic female rats without affecting the PepT1 protein level in either sex. Inducing diabetes with STZ increased PepT1 mRNA and protein levels in female rats; however, in diabetic male rats, the increase in mRNA level was accompanied by a decrease in PepT1 protein level. Treatment of diabetic male rats with insulin partially reversed the effect of diabetes on PepT1 mRNA and protein levels, whereas the same treatment completely restored both PepT1 mRNA and protein to control levels in insulin-treated diabetic female rats. In both nondiabetic male and female rats, insulin treatment had no effect on PepT1 influx rate, and STZ treatment decreased the transporter influx rate. Treatment of diabetic male and female rats with insulin significantly increased PepT1 influx rate; however, complete recovery was found only in diabetic female rats. These results clearly show that insulin and diabetes affected blood glucose level as well as PepT1 activity, expression, and protein levels in a sex-dependent manner. These results suggest that a factor, probably estrogen, could be responsible for the sex-dependent effects of diabetes and insulin in PepT1 level and activity.


2018 ◽  
Author(s):  
Jacques D. Nguyen ◽  
K. M. Creehan ◽  
Tony M. Kerr ◽  
Michael A. Taffe

AbstractAdolescents are regularly exposed to Δ9-tetrahydrocannabinol (THC) via smoking, and, more recently, vaping, cannabis / extracts. Growing legalization of cannabis for medical and recreational purposes, combined with decreasing perceptions of harm, makes it increasingly important to determine the consequences of frequent adolescent exposure for motivated behavior and lasting tolerance in response to THC. Male and female rats inhaled THC vapor, or that from the propylene glycol (PG) vehicle, twice daily for 30 minutes from postnatal day (PND) 35-39 and PND 42-45 using an e-cigarette system. Thermoregulatory responses to vapor inhalation were assessed by radio-telemetry during adolescence and from PND 86-94; chow intake was assessed in adulthood. Blood samples were obtained from additional adolescent groups following initial THC inhalation and after four days of twice daily exposure. Additional groups exposed repeatedly to THC or PG during adolescence were evaluated for intravenous self-administration of oxycodone as adults. Female, not male, adolescents developed tolerance to the hypothermic effects of THC inhalation in the first week of repeated exposure despite similar plasma THC levels. Each sex exhibited tolerance to THC hypothermia in adulthood after repeated adolescent THC with THC greater potency exhibited in females. Repeated-THC male rats consumed more food than their PG treated control group, in the absence of a significant bodyweight difference. Adolescent THC did not alter oxycodone self-administration in either sex, but increased fentanyl self-administration in females. Repeated THC vapor inhalation in adolescent rats results in lasting consequences observable in adulthood.AbbreviationsPG, propylene glycol; THC, Δ9tetrahydrocannabinol;


2021 ◽  
Author(s):  
Fariborz Nowzari ◽  
Farhad Rahmanifar ◽  
Nader Tanideh ◽  
Mohammad Reza Dorvash ◽  
Arezoo Khoradmehr ◽  
...  

Abstract Effects of cottonseed flour in male and female rats’ fertility based on hormonal and histomorphometry changes were studied. Sixty-four Sprague-Dawley adult male and female rats were randomly divided into control and treatment groups. Treatment group was received diets containing cottonseed flour for 35 days. Control group was given standard rat food. Body and testis weights, epididymis semen evaluation indices and serum sex steroid hormones were determined. Histomorphometry alterations of testes and ovary were evaluated. Then, normal female and male rats were mated by rats in both groups and after 35 days, number of pups was measured. However, there was no significant difference in whole body and testes weights, sperm concentration and viability between the control and treatment groups, respectively. Moreover, sperm motility in the treatment rats was significantly lower than the control group. Serum hormones alterations were not significant, but histomorphometry evaluations of testes showed significant changes in the testis structures after chronic consumption of cottonseed flour. In the female rats, body weight did not have significant difference between the treatment and control groups. Histomorphometry data in female ovary showed significant reduction of primary follicle volume and number in the treatment group against control. Follicle stimulating hormone showed insignificant reduction in the treatment group. Number of pups was significantly reduced in the female rats fed by cottonseed flour. Cottonseed flour in rat diet had adverse effects on rat reproduction. Therefore, it can be used as an efficient product for control of the rat population as a natural rodenticide agent.


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