BACKGROUND: Leptin as a cytokine-like hormone is derived from ob gene (one of the major effect genes on birth weight and growth traits) and is secreted by adipose tissue. This hormone with binding to its receptors in the hypothalamus, inhibits food intake and increases energy consumption. OBJECTIVES: There is not any report about expression of leptin gene in response to oral administration of selenium in livestock. In the present study, the effects of selenium nanoparticle and sodium selenite on the transcription of leptin gene in placenta were studied. METHODS: Twenty, four-month pregnant ewes within the same age were selected randomly. During the 21 days leading up to birth, oral administration of selenium nanoparticles (Se NPs) with dosages of 0.05 and 0.10 mg/kg B.W. and sodium selenite with dosage of 0.1 mg/kg B.W. was carried out. At the same time the control group was fed distilled water in equal volume. With sampling of the placenta during childbirth, transcription amount of leptin gene was determined by RT PCR Real Time based on a comparison assay of 2-ΔΔCt. Results: The results of this study showed that leptin gene is expressed in placental tissue. The oral administration of selenium nanoparticle and sodium selenite caused a significant increment in terms of expression of mentioned gene in comparison to the control treatment. Also, there was a significant difference between the supplements, so that the highest leptin gene expression in placenta was observed in selenium nanoparticle treatment with dose of 0.1 mg and then supplement with selenium nanoparticles with dose of 0.05 mg. CONCLUSIONS: Selenium causes an increment of leptin gene expression in placental tissue.

Diabetes is characterized by hyperphagia, and polydypsia. However, the mechanisms by which diabetes produces these effects are not clear. This study was conducted to examine changes in serum insulin and leptin levels in induced-type 1 diabetes mellitus in relation to concomitant changes in body weight, glycemic state and lipid profiles in rats. Moreover, we aimed to clarify that the treatment with lipoic acid (LA) is capable of reversing these effects or not. Ninety-six male rats were divided into 3 groups, control group (32 rats) was considered as normal non-diabetic, 64 rats were subcutaneously injected with alloxan (120 mg/kg.b.wt) for induction of diabetes. Then the diabetic rats were divided into two equal subgroups, the first is diabetic group that was not treated with LA, and the other is LA-treated diabetic group that was treated with LA at a dose 100 mg/kg b.wt / day for four weeks. Body weight, serum lipid profile, glucose, insulin, homeostasis model assessment– insulin resistance (HOMA-IR) and leptin were measured. The data showed significant increase in serum triacylglycerol, total cholesterol and glucose levels as well as HOMA-IR while significant decrease in the mean body weight gain, serum insulin and leptin levels in diabetic group in comparison with control group. The treatment with lipoic acid led to significant decrease in serum fasting and postprandial glucose, triacylglycerol and total cholesterol levels as well as slight decreased HOMA-IR with significant increased levels of serum insulin and leptin in comparison with diabetic group. It could be concluded that alloxan-induced diabetes led to hyperglycaemia, insulin resistance, hyperlipideamia and hypoleptinamia. Moreover, treatment with lipoic acid ameliorates these changes and improves insulin sensitivity.

The aim of this study was to evaluate the effect of negative energy balance (NEB) on the final growth of the dominant ovarian follicle in Holstein cows. Cows at 14 to 21 d postpartum from an intensive dairy farm were randomly selected and allocated into a positive energy balance group (PEB, with β-hydroxybutyric acid (BHBA) level < 1.2 mmol/L, n = 15) and an NEB group (BHBA > 1.2 mmol/L, n = 15). Plasma samples were collected at 21, 50 and 55 d postpartum to assess the concentrations of energy metabolites, minerals, hormones and cytokines. Ovaries were examined by transrectal ultrasound on days 50 and 55 (120 hours later) to evaluate the diameter of the largest follicle. Compared with PEB cows, there were a more severe body condition loss and a lower milk yield in NEB cows (P < 0.05) and these had greater concentrations of plasma BHBA, non-esterified fatty acids, triglycerides, urea nitrogen, growth hormone, interleukin 6, and fibroblast growth factor 21 and lesser concentrations of plasma glucose, total cholesterol, insulin, insulin-like growth factor 1, insulin-like growth factor binding protein 3, leptin, brain-derived neurotrophic factor and angiopoietin-like protein 8 on d 21 (P < 0.05), while plasma minerals were not affected by energy status (P > 0.05). These changes persisted until the end of the study period (50–55 days postpartum) resulting in a lower follicular growth rate for cows in the NEB than the PEB group. These observations indicate that follicular growth rate is associated with measurable changes in energy metabolite, hormone and cytokine concentrations caused by early postpartum NEB.

Objective: House musk shrew (Suncus murinus), a small experimental animal with low body fat, may be a possible model for human lipodystrophy. Leptin is an adipocyte-derived hormone thought to have an important role in the pathophysiology of lipodystrophy. The objectives of this study were to clarify the structure and distribution of suncus leptin.Materials and methods: To determine the primary structure of suncus leptin, we cloned the suncus Lep cDNA using the rapid amplification of cDNA ends method. The obtained amino acid (aa) sequence was compared with other mammals and the protein structure prediction was performed.Results: The suncus Lep cDNA encodes 170 aa. The putative suncus leptin precursor has a predicted signal peptide of 21 aa, and the mature leptin comprises 149 aa. The mature leptin is 75%82% homologous to that of other species. Insertion of the three aa, VPQ, not seen in other mammals was found. This VPQ insertion is thought to be due to a nucleotide insertion of nine bases by slippage-like microindels. The predicted 3D structure of suncus leptin exhibited a typical four a-helix structure, however, the VPQ region protruded compared with human leptin. LepmRNA expression was observed only in white and brown adipose tissues. Conclusion: This study revealed the structure and distribution of suncus leptin. Because the addition of VPQ, which is not found in other mammals, was observed, suncus leptin attracts attention to its physiological action, and to the possibility of being a model of human lipodystrophy. [J Adv Vet Anim Res 2019; 6(1.000): 1-8]

Buffaloes mostly suffer from delayed puberty, anestrus, sub–estrus, summer infertility, prolonged inter-calving interval and postpartum uterine disorders. Nesfatin-1 and Leptin are directly or indirectly related with body weight (BW), feed parameters and regulation of puberty. The objective of this study was to investigate the influence of Nesfatin-1 and Leptin in pubertal and non-pubertal Murrah buffalo heifers. The Murrah buffalo heifers (n=13) were randomly selected and divided into two groups; pubertal group (PG) and non-pubertal group (NG). Heifers with plasma progesterone (P4) level of ≥1 ng/mL were classified as PG. Blood samples were collected at fortnight intervals for analysis of plasma Nesfatin-1, Leptin, P4, glucose and non-esterified fatty acids. Body weight, dry matter intake and feed conversion efficiency were recorded at fortnight intervals. The mean (±SEM) plasma Nesfatin-1, Leptin, P4, BW and feed conversion efficiency (%) were significantly (P<0.01) higher in PG as compared to NG. Dry matter intake by the heifers was also significantly (P<0.001) higher in PG than NG. Plasma metabolites (glucose and NEFA) did not differ significantly between the groups. The findings of this study suggest that Nesfatin-1 and Leptin have indispensable role in the onset of puberty in buffalo heifers by affecting BW and feed parameters.

Objective--To evaluate 5 commercially available ELISAs for determination of leptin concentrations in serum samples from dogs. Sample Population--Serum samples from overweight-obese and thin–ideal weight clientowned dogs. Procedures--Serum samples with high and low leptin concentrations (n = 7 samples each) were used for validation of the assays. Intra- and interassay precision, linearity under dilution, spiking recovery, and limit of quantification were determined. In addition, leptin concentrations in thin–ideal weight (n = 8) and overweight-obese (37) dogs were quantified. Results--Use of 2 of the 5 ELISAs (A and B) revealed reactivity with canine leptin. Intra-and interassay coefficients of variation were < 6.1% and 76%, respectively, for assay A and 14.0% and 13.7%, respectively, for assay B. In assays A and B, dilutions of canine serum pools were used to determine linear regression equations. Recoveries were 77% to 101% for assay A and 67% to 125% for assay B. Significant differences in leptin concentrations between thin–ideal weight and overweight-obese dogs were detected only when analyzed with assay A. Conclusions and Clinical Relevance--Among 5 leptin ELISAs evaluated, a canine-specific leptin ELISA had adequate precision, linearity, and ability to discriminate between high and low leptin concentrations corresponding to overweight-obese and thin–ideal weight dogs, respectively.

Objective: To determine associations between serum concentrations of omega-3 polyunsaturated fatty acids and concentrations of adiponectin, leptin, and insulin in healthy cats. Animals: 56 healthy adult client-owned cats. Procedures: Body condition score (BCS) was determined, and blood samples were collected after food was withheld for 12 hours. Serum was harvested for fatty acid analysis and measurement of serum concentrations of adiponectin, leptin, insulin, glucose, triglyceride, and cholesterol. Results: 1 cat was removed because of hyperglycemia. Significant interaction effects between BCS and serum concentrations of eicosapentaenoic acid (EPA) were detected for the analyses of associations between EPA and serum concentrations of adiponectin, insulin, and triglyceride. Cats were categorized into nonobese (BCS, 4 to 6 [n = 34 cats]) and obese (BCS, 7 to 8 [21]) groups; serum concentrations of EPA were directly associated with concentrations of adiponectin and inversely associated with concentrations of insulin and triglyceride in obese cats and were directly associated with concentrations of leptin and inversely associated with concentrations of adiponectin in nonobese cats. Additionally, serum concentrations of docosahexaenoic acid were directly associated with concentrations of adiponectin in obese cats. No significant associations between serum concentrations of docosahexaenoic acid or α-linolenic acid were detected in the analyses for all cats. Female cats had higher serum concentrations of adiponectin and lower concentrations of glucose than did male cats. Increased age was associated with a small increase in serum concentrations of leptin. Conclusions and Clinical Relevance: EPA may ameliorate the decrease in adiponectin and the increase in insulin and triglyceride concentrations in obese cats.

OBJECTIVE To determine effects of hydrocortisone administration on serum leptin and adiponectin concentrations, abdominal fat distribution, and mRNA expression of leptin and adiponectin in abdominal adipose tissue of dogs. ANIMALS 12 healthy dogs. PROCEDURES Dogs received hydrocortisone (8.5 mg/kg; n = 6) or a placebo (6) orally every 12 hours for 90 days. Serum leptin and adiponectin concentrations were measured with a canine-specific ELISA on the day before (day 0; baseline) and during (days 1, 3, 7, 30, 60, and 90) administration. On days 0, 30, 60, and 90, abdominal fat mass was quantified with CT, and mRNA expression of leptin and adiponectin in abdominal fat was analyzed by use of a PCR assay. RESULTS Hydrocortisone administration resulted in an increase in visceral fat mass on days 60 and 90, compared with the mass at baseline. Visceral fat mass at the level of L3 increased during hydrocortisone administration. Serum leptin concentration began to increase on day 1 and was significantly higher than the baseline concentration on days 30 and 60. Serum adiponectin concentration on days 30, 60, and 90 was significantly lower than the baseline concentration. Leptin and adiponectin mRNA expression in abdominal fat was greater on day 30, compared with expression at baseline, but lower on days 60 and 90, compared with expression on day 30. Serum leptin concentration and visceral fat mass were correlated. CONCLUSIONS AND CLINICAL RELEVANCE Hydrocortisone administration affected abdominal fat distribution and serum leptin and adiponectin concentrations through dysregulation of leptin and adiponectin expression.

OBJECTIVE To evaluate the usefulness of intestinal biomarkers in determining the presence of intestinal epithelial damage in neonatal calves with diarrhea caused by 4 etiologic agents. ANIMALS 40 neonatal calves that were healthy (n = 10) or had diarrhea (30). PROCEDURES The study was a cross-sectional study. Results of hematologic analyses and serum concentrations of intestinal fatty acid–binding protein (I-FABP), liver fatty acid–binding protein (L-FABP), trefoil factor 3 (TFF-3), Claudin-3 (CLDN-3), γ-enteric smooth muscle actin (ACTG2), intestinal alkaline phosphatase (IAP), interleukin-8 (IL-8), platelet-activating factor (PAF), and leptin (LP) were compared among calves grouped according to whether they were healthy (control group; G-1) or had diarrhea caused by K99 Escherichia coli (G-2; n = 10), bovine rota- or coronavirus (G-3; 5 each), or Cryptosporidium spp (G-4; 10). RESULTS Across the 3 time points at which blood samples were obtained and evaluated, the groups of calves with diarrhea generally had markedly higher mean serum concentrations of L-FABP, TFF-3, IAP, IL-8, and LP, compared with the control group. In addition, G-2 also consistently had markedly higher mean serum concentrations of I-FAB and ACTG2 and lower mean serum concentrations of CLDN-3, compared with the control group. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that degree of intestinal epithelial damage differed among calves grouped by the etiologic agent of diarrhea and that such damage might have been more severe in calves with diarrhea caused by K99 E coli. Additionally, our results indicated that serum concentrations of I-FABP, L-FABP, TFF-3, IAP, IL-8, ACTG2, LP, and CLDN-3 were useful biomarkers of intestinal epithelial damage in calves of the present study.

Objective: To determine associations between serum concentrations of omega-3 polyunsaturated fatty acids or body condition and serum concentrations of adiponectin, leptin, insulin, glucose, or triglyceride in healthy dogs. Animals: 62 healthy adult client-owned dogs. Procedures: Body condition score and percentage of body fat were determined. Blood samples were collected after food was withheld for 12 hours. Serum was harvested for total lipid determination, fatty acid analysis, and measurement of serum concentrations of adiponectin, leptin, insulin, glucose, and triglyceride. Associations between the outcome variables (adiponectin, leptin, insulin, glucose, and triglyceride concentrations) and each of several variables (age, sex, percentage of body fat, and concentrations of total lipid, α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) were determined. Results: Serum concentrations of docosapentaenoic acid were significantly positively associated with concentrations of adiponectin and leptin and negatively associated with concentrations of triglyceride. Serum concentrations of α-linolenic acid were significantly positively associated with concentrations of triglyceride. No significant associations were detected between serum concentrations of eicosapentaenoic acid or docosahexaenoic acid and any of the outcome variables. Percentage of body fat was significantly positively associated with concentrations of leptin, insulin, and triglyceride but was not significantly associated with adiponectin concentration. Age was positively associated with concentrations of leptin, insulin, and triglyceride and negatively associated with concentrations of adiponectin. Sex did not significantly affect serum concentrations for any of the outcome variables. Conclusions and Clinical Relevance: Docosapentaenoic acid may increase serum concentrations of adiponectin and leptin and decrease serum triglyceride concentration in healthy dogs.