Differential gene expression of three nitric oxide synthases is consistent with increased nitric oxide in the hindbrain of broilers with cold-induced pulmonary hypertension

Canine sperm motility is associated with telomere shortening and changes in expression of shelterin genes

BACKGROUND

Motion quality is a critical property for essential functions. Several endogenous and exogenous factors are involved in sperm motility. Here, we measured the relative telomere length and evaluated the gene expression of its binding-proteins, shelterin complex (TRF1, TRF2, RAP1, POT1, TIN2, and TPP1) in sperm of dogs using relative quantitative real-time PCR. We compared them between two sperm subpopulations with poor and good motion qualities (separated by swim-up method). Telomere shortening and alterations of shelterin gene expression result from ROS, genotoxic insults, and genetic predisposition.

RESULTS

Sperm kinematic parameters were measured in two subpopulations and then telomeric index of each parameter was calculated. Telomeric index for linearity, VSL, VCL, STR, BCF, and ALH were significantly higher in sperms with good motion quality than in sperms with poor quality. We demonstrated that poor motion quality is associated with shorter telomere, higher expression of TRF2, POT1, and TIN2 genes, and lower expression of the RAP1 gene in dog sperm. The levels of TRF1 and TPP1 gene expression remained consistent despite variations in sperm quality and telomere length.

CONCLUSION

Data provided evidence that there are considerable changes in gene expression of many shelterin components (TRF2, TIN2, POT1and RAP1) associated with shortening telomere in the spermatozoa with poor motion quality. Possibly, the poor motion quality is the result of defects in the shelterin complex and telomere length. Our data suggests a new approach in the semen assessment and etiologic investigations of subfertility or infertility in male animals.

Effect of sage (Salvia officinalis L.) extract in antioxidant status and intestinal morphology of pulmonary hypertensive chickens

OBJECTIVES

The effects of dietary sage on the growth performance, antioxidant status, intestinal mucosa morphology, and pulmonary hypertensive response were investigated in broiler chickens with pulmonary hypertension.

METHODS

Chicks (Ross 308) were reared under cold stress for 35 days and treated with 0.05% vitamin C (positive control) and 0 (control), 0.1 or 0.2% sage extracts, then performance, oxidant and antioxidant status, and intestinal morphology were evaluated.

RESULTS

The index of pulmonary hypertension (RV:TV) was decreased, and weight gain (days 22-35) was increased in all treatments (except for sage 0.1%) compared with control (P < 0.05). Lipid peroxidation was decreased, whereas the activity of antioxidant enzymes (GPX, CAT, and SOD) was increased in the sage 0.2% group compared with control (P < 0.05). In the lung, SOD, CAT, and GPX transcripts were decreased in the sage 0.2% group compared with control (P < 0.05). In the right ventricle of the heart, SOD and CAT transcripts were increased in the sage 0.2% group compared with other groups of chickens, whereas GPX transcript was decreased (P < 0.05). The jejunal villus length in the chickens fed sage was significantly lower than in control (P < 0.05). The ileal villus width, villus surface area, and lamina proporia thickness in the chickens fed sage (0.2%) were increased compared with control (P < 0.05).

CONCLUSIONS

Dietary supplementation of sage (0.2%) could modulate pulmonary hypertensive response, improve antioxidant status (enzymatic activity), intestinal morphometry, and absorptive surface in the broiler chickens.

Cardiac telomere attrition following changes in the expression of shelterin genes in pulmonary hypertensive chickens

1. The alterations of relative telomere length and expression of shelterin genes (TRF1, TRF2, RAP1, POT1, and TPP1) were evaluated from the chickens' right heart ventricle in the early and last stages of cold-induced pulmonary hypertension (PHS) at 21 and 42 d of age.2. The relative telomere length in the right ventricular tissues was significantly shorter in the PHS group of broilers than in the control group at 42 d, but did not statistically change at 21 d of age. There was a significant negative correlation between relative telomere length and RV:TV ratio in the broilers at 42 d of age.3. The relative expression of POT1, RAP1 and TPP1 genes in the right ventricular tissues was significantly lower in the PHS group than in the control group at 21 d. The relative expression of the TRF2 gene was only higher in the PHS group of broilers than control at 42 d. The mRNA level of the TRF2 gene exhibited a significant positive correlation with RV:TV ratio at 42 d.4. It was concluded that most shelterin genes are dysregulated in the early stage of PHS (right ventricular hypertrophy) while telomere attrition occurs only at the last stage (heart dilation/failure).

Changes in the expression of cardiac genes responsive to thyroid hormones in the chickens with cold-induced pulmonary hypertension

Cold stress is an environmental cause of pulmonary hypertension syndrome (PHS) in broiler chickens. This factor could increase the rate of metabolic activity via thyroid hormones (T3 and T4). To evaluate the effect of these hormones on the heart, the plasma concentration of T3, T4, and the gene expression of their receptors (THRα and THRβ) and many contractile proteins (ACTC1, MHCα, MHCβ, RYR2, SERCA2, THRα, THRβ, and troponin I) were measured in the right ventricle in 2 periods of age (21 and 35 d). Plasma T3 concentration was significantly higher in the PHS group of chickens than in the control one at 21 and 35 d while plasma T4 did not change. The relative expression of MHCα, RYR2, SERCA2, and THRα genes in the right ventricle tissues was only higher in PHS group of broilers than control group at 21 d (P < 0.05) whereas the expression of ACTC1, MHCβ, and troponin I did not differ at 2 periods of age. The positive correlations between MHCα, RYR2, SERCA2, and T3, THRα were confirmed. The expression of THRβ gene was only higher in PHS group of broilers than control at 35 d (P < 0.05). The data determined that cold stress could increase thyroid hormones and the gene expression of their receptor (THRα) in the pick of chicken growth (21 d) that they themselves elevates the expression of many genes related to contractile elements (MHCα, RYR2, and SERCA2), leading to adaptive right ventricle hypertrophy.

Effect of Shirazi thyme on oxidant status and absorptive surface area of the intestine in cold-induced pulmonary hypertensive broiler chickens

The effects of Shirazi thyme as a medicinal plant on oxidant status (lipid peroxidation, protein oxidation, total antioxidant capacity, and catalase activity) and absorptive surface area were measured in three segments of the small intestine in cold-induced pulmonary hypertensive chickens. Birds were reared at four groups (thyme 0, 0.25, 0.50, and 1.00 % of diet) for 42 days. To induce pulmonary hypertension, the temperature was gradually decreased. The body weight was increased in thyme-0.25% birds compared to control ones, while it was decreased in thyme-1% of birds. The feed consumption was only increased in thyme-1.00% birds. The feed conversion ratio was lower in thyme-0.25% birds and higher in thyme-1.00% birds than control ones. The duodenal and jejunal villus surface area was lower in thyme-1.00% birds than control ones, while it was greater in the thyme-0.50% birds. The ileal villus surface area and duodenal lamina propria thickness were also greater in thyme-0.50% birds. Lipid peroxidation was only decreased in the duodenum and ileum of thyme-0.50% birds compared to control ones, whereas it was increased in the duodenum and jejunum of thyme-1.00% birds. Catalase activity was only elevated in the duodenum and jejunum of thyme-1.00% fed chickens. Total antioxidant capacity was increased in the duodenum, jejunum, and ileum of thyme-0.50% birds. It is concluded that the Shirazi thyme has beneficial effects on growth performance, intestinal absorptive surface area / secretory system, and pulmonary hypertension response at low doses (0.25 and 0.50% of diet), whereas high dose (1.00% of diet) of this plant may be toxic.

Differential expression of genes implicated in liver lipid metabolism in broiler chickens differing in weight

1. Lipid parameters and expression of ACACA, APOA1, CPT1A, FASN, FOXO1, LIPG, PPARα and SIRT1 genes involved in lipid metabolism were investigated in two groups of high (HW) and low (LW) weight broilers from the same strain.2. Blood cholesterol and liver triglyceride levels were significantly increased in HW chickens compared to LW broilers, while other parameters, i.e. blood triglyceride, blood HDL/LDL, liver cholesterol and total liver fat showed no significant changes in either group.3. The relative expression of ACACA, APOA1 and CPT1A genes was significantly lower in the liver tissues of HW broilers than in the LW group. The mRNA levels of these three genes showed a significant negative correlation with abdominal fat deposition and live weight of broilers. However, relative expression of FASN, FOXO1, LIPG, PPARα and SIRT1 hepatic genes did not differ among broilers.4. It was concluded that, of eight hepatic genes implicated in lipid metabolism, only the expression of three (ACACA, APOA1 and CPT1A) were significant for fat and leanness within the same strain of chicken. Since reducing body fat is a major goal in the broiler industry, these data can provide fresh insight into the molecular processes underlying the regulation of fat deposition in broilers.

Brain renin-angiotensin system in broiler chickens with cold-induced pulmonary hypertension

1. The relative expression of angiotensinogen (AGT), renin, angiotensin-converting enzyme (ACE) and angiotensin II type 1 receptor (AT₁R) was determined using quantitative real-time PCR on tissue from the brain (forebrain, midbrain and hindbrain) to investigate the effect of cold-induced pulmonary hypertension syndrome (PHS) in broilers aged 42 days. Brain angiotensin II (Ang II) and AT₁R levels were measured using enzyme immunoassay. 2. The right ventricle/total ventricles (RV/TV) ratio of the heart was increased in broilers exposed to cold stress (PHS group) at the end of the experiment. 3. ACE and renin transcripts in three parts of the brain were significantly increased in the PHS group at 42 d of age compared to controls while AGT transcript was significantly increased only in the hindbrain of PHS birds. The amount of AT1R transcript did not differ between control and PHS groups. 4. The amount of Ang II significantly decreased only in the midbrain of PHS birds compared with controls while the amounts of AT₁R were not different between treatments in the three segments of the brain. 5. It was concluded that brain gene expression of AGT (in the hindbrain), renin, and ACE was upregulated in broilers with PHS whereas Ang II and AT1R levels were not changed. These results provided evidence of diminished involvement of the renin-angiotensin system in the pathogenesis of chicken pulmonary hypertension.

Comparative Expression Analysis of HSP70, HSP90, IL-4, TNF, KITLG and KIT-receptor Gene between Varicocele-Induced and Non-Varicocele Testes of Dog

Background

This study was designed to create an experimental varicocele model by a simple surgical procedure in dog with minimum invasion and to investigate the effect of varicocele-induced infertility on the expression of six related genes (HSP90, HSP70, IL-4, TNF, KITLG and KIT receptor).

Materials and Methods

In this experimental study, the proximal part of the pampini-form plexus of dog testes was partially occluded without abdominal incision which was confirmed by venographic examination. To evaluate varicocele in its acute form, dogs were castrated after 15 days and testes were dissected. Histopathologic evaluation was undertaken and the relative expression of the six genes was assessed by quantitative realtime polymerase chain reaction (PCR).

Results

Microscopic changes showed tubule degeneration. The Johnson score was significantly decreased in the varicocele testes when compared with non-varicocele testes. Expressions of HSP90, TNF, KITLG and the KIT-receptor gene were significantly downregulated (P=0.029, 0.047, 0.004 and 0.035 respectively) in varicocele-induced testes while HSP70 was upregulated (P=0.018). IL-4 did not show differential expression (P=0.377).

Conclusion

We conclude that partial occlusion of the proximal part of the pampiniform plexus induces varicocele in the testis of dog. Differential expression of the mentioned genes may be responsible for the pathophysiology of varicocele and related subfertility.