T4 Concentrations Research Articles

Thyroid hormones in female and male reproduction with special reference to dogs and cats

Thyroid hormones have an important function in numerous physiological processes in humans and animals, including the regulation of metabolism, growth and development of individual and reproductive function. The thyroid hormones, triiodothyronine (T3) and thyroxine (T4), have a direct effect on the reproductive organs and an indirect effect in interaction with other hormones. Thyroid hormones influence the reproductive system by regulating metabolism and tissue development of the ovaries, uterus and placenta. Changes in the serum concentrations of T3 and T4 lead to disturbances in overall body function. Thyroid dysfunction, including hypothyroidism and hyperthyroidism, can lead to significant reproductive problems. The aim of this review was to describe the functions of thyroid hormones and the effects of hypothyroidism and hyperthyroidism on the animal reproductive system. Hypothyroidism is often caused by autoimmune diseases such as lymphocytic thyroiditis, and is associated with later puberty, reduced fertility and abnormalities in reproductive organ development. Hypothyroidism can lead to a prolonged interval, absent cycles, silent oestrus cycles, prolonged oestrus bleeding, and a lack of libido, with the occurrence of infertility, miscarriages, stillbirths and mummified foetuses. In males, hypothyroidism leads to a decrease in libido, semen quality, ejaculate volume, testicular atrophy, hypospermia and azoospermia. Hyperthyroidism, on the other hand, is usually the result of thyroid cancer, which produces excessive amounts of thyroid hormones. Increased concentrations of thyroid hormones lead to disturbances in the physiological balance of reproductive hormones, irregular oestrus cycles, anovulation and reduced fertility, as well as a decrease in the weight of the ovaries and the number of healthy follicles, with a simultaneous increase in the number of atretting follicles. The effects of hyperthyroidism on male fertility include disorders of spermatogenesis, changes in sex hormone levels and changes in sperm quality, such as hypospermia, oligozoospermia, asthenozoospermia and teratozoospermia. It is important to diagnose and treat thyroid disorders in time in order to prevent negative effects on fertility and reproduction in animals.

Influence of endophytic fungi treatments on aluminum contents in Vernicia montana seedlings and soils under different concentrations of aluminum stress

Although leveraging the interaction with endophytic fungi is an efficient and environment-friendly strategy for plants to enhance growth and resistance, how different endophyte species influence host plants’ resilience in adverse conditions remain comparatively unclear. In order to explore the effect of endophytic fungi on the aluminum resistance of woody host plants, Vernicia montana seedlings were subjected to different aluminum concentrations (T0, T1, T2, T3, T4) in this study. The aluminum contents in roots, leaves and rhizospheric soil of V. montana seedlings were determined after applying endophyte suspensions of Pestalotiopsis (NP), Alternaria (LA), Penicillium (QP), Coniothyrium (DC) and Thermophilic (ST) spp. The results showed that aluminum stress treatment, endophytic fungi treatment and their interaction had significant effects on aluminum content in leaves, aluminum content in roots, aluminum content in rhizospheric soil, and the transport and retention rate of aluminum ions in soil-root-leaf. With the increase of aluminum concentrations, the aluminum content in leaves of V. montana increased in the endophyte treatments of LA and ST, decreased in CK, NP and DC, or had marginal variation in QP treatment. Compared with T0, four endophyte treatments of LA, QP, DC and ST significantly reduced root aluminum content under T4 concentration (P < 0.05), contrary to the results of NP treatment. Endophyte treatments significantly increased root aluminum content of V. montana under T1 concentration (P < 0.05). The foliar Al content in fungi-inoculated seedlings was significantly lower than that of the non-inoculated ones under T0 and T3 levels (P < 0.05), the LRR is less than 1, while the opposite trend was observed under T2 and T4 treatments. The aluminum transport coefficient TFsoil-root and TFroot-leaf increased in different proportions under the same aluminum concentration. The findings indicate that the application of endophytic fungi change the aluminum contents and transport from rhizospheric soil, roots to leaves. The specific effects of endophytic fungi vary with the degree of aluminum stress and the fungi genus. The study proves that inoculation of endophytic fungi can improve the aluminum tolerance of host plants, and thereby play an important role in promoting the sustainable development of forestry.

Propylthiouracil thyroid manipulation positively affects the metabolic adaptability of primiparous dairy cows to early lactation requirements

The study examined effects of thyroid manipulation with propylthiouracil (PTU) on the metabolic adaptability of transitional dairy cows to early lactation. The study included 30 primiparous Holstein-Friesian cows, which were divided into two groups: PTU+ (n = 15; received orally 4 mg/kg PTU during 20 days before expected calving) and PTU− (n = 15; did not receive orally PTU). Blood was sampled from each cow consecutively from − 20, − 17, − 13, − 5, − 4, − 3, − 2, and − 1 days before the expected term of calving, calving day (0), and + 1, + 2, + 3, + 4, + 5, + 10, + 15, + 30 and + 60 days after the calving to measure thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), insulin, glucose, beta-hydroxybutyrate (BHB), bilirubin, total protein and albumin concentrations. Liver samples were biopsied at −7 ± 2 and +7 day relative to calving from both groups of cows to determine deiodinase (DIO) expressions and fat and glycogen content. Additionally, milk yield was monitored during the first 60 days of lactation. PTU successfully induced thyroid suppression by significantly reducing T3 and T4 concentrations and hepatic DIO1 expressions and caused PTU+ cows to have significantly higher insulin and glucose concentration in the precalving period. After calving, PTU+ cows had higher insulin and glucose concentration, liver glycogen content and overall milk production, lower BHB concentration, BCS loss, and liver fat deposits. Accordingly, cows treated with PTU have a more favourable energy balance and metabolic adaptation to early lactation.

Apoptosis and genotoxicity effects of Zygophyllum album and Suaeda palaestina extracts on Ehrlich solid carcinoma in mice

BackgroundVarious medicinal plants and their bioactive compounds exhibited promising anticancer activities by inducing apoptosis, inhibiting angiogenesis, and modulating several signaling pathways in cancer cells. This study aims to assess whether two medicinal plant extracts have anticancer properties, Suaeda Palaestina and Zygophyllum album.MethodsThis study used Ehrlich solid tumor mice as its in vivo model. We divided male mice into five groups (n = 5 per group). Group I was used as a control for Ehrlich ascites carcinoma (EAC). Groups 2 and 3 were given Z. album extract 180 mg/kg and 360 mg/kg body weight intraperitoneally. Groups 4 and 5 were given the same dose of S. palaestina and treated three times a week for 2 weeks, starting on day 10 after EAC implantation. After 3 weeks, we collected blood samples and thigh skeletal muscle, homogenized them, and processed them for analysis. The results showed that Ehrlich solid rats (EST) treated with low-dose dichloromethane extracts from Z. album and S. palaestina had significantly smaller tumor sizes than the control group. Protein expression levels of p53, caspase 3, and Bcl-2 were quantified by western blotting.ResultsThe extracts from both plants induced the hunger mechanism, leading to increased expression of p53 and caspase 3 and decreased expression of Bcl-2 at the protein level in EST mice treated with Z. album and S. palaestina. In addition, the comet assay indicated that these plants have a genotoxic potential for solid tumor cells. The T3 and T4 levels in EST blood samples revealed that both plants had significantly reduced the concentration of T3 and significantly increased T4 compared to the EST mice untreated group. Furthermore, these results showed that Z. album and S. palaestina had antiproliferative effects in EST mice through apoptosis-mediated genotoxicity.ConclusionsThese findings indicated that S. palaestina and Z. album could be considered potential natural sources of anticancer agents.

8747 A Rare Receptor Resistance with Paradoxical Outcomes!

Abstract Disclosure: I. Patoli: None. S. Batool: None. A.S. Gill: None. A. Makdissi: None. Introduction: Resistance to thyroid hormone receptor is an uncommon cause of abnormal TFTs. (1) We present an interesting case of THRB resistance with cardiac arrhythmia (CA). Clinical Case: 46-year-old man with history of atrial fibrillation (Afib) was referred to endocrinology for evaluation of abnormal TFTs and thyroid nodule. He had a recent hospital admission for Afib with rapid ventricular response; 3 years ago, he was treated with amiodarone for 2 months. TFTs revealed normal TSH of 1.375, elevated FT4 of 2.76 (normal ranges 0.55-4.78 and 0.89-1.76, respectively). Neck CT scan showed large peripherally enhancing centrally necrotic mass with calcification encompassing nearly the entirety of left thyroid lobe measuring 2.2 x 3.6 x 4.6 cm. A 0.8 cm hypodensity within right thyroid lobe also visualized. Thyroid ultrasound showed nodules bilaterally with the largest one in the lower pole of left lobe. FNA biopsy showed Bethesda category- II benign, benign appearing follicular cells and abundant colloid. Repeat labs showed similar results with persistently elevated free T4 (2.56) with equilibrium dialysis, normal alpha subunit, normal TSH (2.14) with human anti-mouse antibody (HAMA) antibody was negative. Alpha subunit:TSH ratio was &amp;lt;1. He remained clinically euthyroid over the course of 1.5 year but repeat labs at that time indicated that TSH had increased to 17 with elevated free T4 (2.6) . MRI brain ruled out TSH secreting adenoma. He reported thyroid abnormalities in son and brother but was unable to provide details. He was referred for genetic screening which showed THRB with pathogenic variant: c.9628&amp;gt; G (p.Y321C). Conclusion: THRB resistance is an uncommonly diagnosed modality in endocrinology. The genes encoding thyroid hormone receptors are THRα gene and THRβ gene (2). Patients with inherited THRB pathogenic variants present with resistance to thyroid hormone and often enlarged thyroid gland. Interestingly, despite having receptor resistance, patients may manifest with CA. This is hypothesized to be due to elevated T4 and T3 concentration in the heart which primarily has higher expression of THRA (3). The diagnosis of thyroid hormone resistance is important to avoid treating asymptomatic patients where treatment is not warranted.

6669 Association Between Serum Levels of Thyroid Function and Per- and Polyfluoroalkyl Compounds Concentrations in Central Precocious Puberty in Girls

Abstract Disclosure: Y. Li: None. Y. Xing: None. X. Yin: None. J. Yang: None. S. Zang: None. T. Dong: None. Y. Pan: None. J. Dai: None. P. Li: None. Background: Exposure to per- and polyfluoroalkyl substances (PFASs) may interfere with thyroid function in the general population and disturb the timing of puberty onset. Objectives: We investigated the possible relationship between PFASs and thyroid hormone (THs) exposure in girls with central precocious puberty (CPP). Methods: In a prospective study initially established for assessing CPP, 627 serum samples were collected with (n = 226) and without (n = 401) CPP. The concentrations of 25 PFASs, thyroxin (T4), 3,5,3’-triiodothyronine (T3), and 3,3’,5’-triiodothyronine (rT3) were measured. We used logistic regression to examine the association of THs with the odds of having CPP and multiple linear regression to analyze the associations between THs and various PFASs in the CPP and control groups. Results: The levels of T4 in the CPP group were significantly lower than those in the control group, and the levels of T3 and rT3 were significantly higher than those in the control group. After adjusting for confounders, T3 concentrations were associated with 1.526-fold increased odds of having CPP [odds ratio (OR) = 1.526, 95% confidence interval (CI):1.216-1.914]. In the CPP cohort, perfluoroheptanoic acid (PFHpA), perfluoro (2-ethoxyethane) sulphonic acid (PFEESA), and fluorotelomer phosphate diester (6:2/8:2 diPAP) were inversely associated with T3; perfluorobutanoic acid (PFBA) was inversely associated with T4, and PFEESA and 6:2/8:2 diPAP positively associated with T4; PFBA was positively associated with rT3, and perfluorooctane sulfonic acid (PFOS) was inversely associated with rT. In the control cohort, perfluorobutanesulfonic acid (PFBS) was positively associated with T3, and PFEESA and 6:2/8:2 diPAP were inversely associated with T3, and these PFASs had an adverse association with T4. Perfluorohexanoic acid (PFHxA) was positively associated with rT3, and 6:2/8:2 diPAP was negatively associated with rT3. Conclusion: In this study, different measurements of PFASs and THs were observed in the CPP and control groups. Discrepancies in exposure to PFASs were associated with THs in the CPP cohort and healthy girls. Further research is necessary to investigate the mechanism by which PFASs affect the timing of puberty onset and thyroid function. Presentation: 6/1/2024

Influence of sire plane of nutrition and targeted body weight gain on ewe lamb growth, glucose metabolism, and ovarian reserve.

Rambouillet rams were managed on either a positive (POS; gain 12% body weight [BW]; n = 8), maintenance (MAINT; maintain BW; n = 8), or negative (NEG; lose 12% BW; n = 8) plane of nutrition before breeding. Rams were bred to ewes (n = 10 per ram) that were managed similarly throughout gestation, and lambs were fed a common diet postnatally. Two ewe lambs (7.6 ± 0.02 months of age, BW = 47.1 ± 1.17kg) from each sire were selected and within pair, randomly assigned to be managed for a moderate (MOD, 0.11kg/d; n = 23) or accelerated (ACC, 0.20kg/d; n = 22) rate of gain for 56 d. Ewe lamb BW was recorded on a weekly basis and blood was collected on d 0, 28, and 56 for analysis of insulin-like growth factor 1 (IGF-1), triiodothyronine (T3), thyroxine (T4), glucose, blood urea nitrogen (BUN), and non-esterified fatty acids (NEFA). Intravenous glucose tolerance tests (IVGTT) were conducted from d -7 to -4 and d 57 to 64. A unilateral ovariectomy was performed and ovarian follicles were staged and counted macro and microscopically. Sire treatment × day and ewe treatment × day interactions were present for BW (P ≤ 0.05), where POS had slower growth than MAINT and NEG, and tended (P = 0.10) to have reduced average daily gain (ADG) when managed at an accelerated rate of gain.By design, ACC had greater BW and ADG than MOD (P < 0.05). Concentrations of IGF-1 and T4 were greater in ACC than MOD (P ≤ 0.05), and NEG tended to have greater concentrations of IGF-1 than POS and MAINT (P = 0.08). At the first IVGTT, concentration of insulin was influenced by a sire treatment × time interaction (P ≤ 0.05), suggesting impaired secretion in NEG-sires ewes, but no differences in area under the curve (AUC) for glucose, insulin, or their ratio (P ≥ 0.11). No interactive effects of sire and ewe treatment (P ≥ 0.52) were observed at the second IVGTT, but insulin and insulin:glucose ratio were influenced by sire treatment × time (P ≤ 0.02), as NEG had greater insulin concentration at 60min than MAINT (P = 0.03) and greater AUC than POS and MAINT (P ≤ 0.04). No differences in ovary size, weight, or total counts of macro and microscopic follicles were observed (P ≥ 0.23). Ewes fed ACC had a greater number of small surface follicles (P = 0.02), whereas MOD tended to have a greater number of large surface follicles and tertiary follicles (P < 0.06). These findings suggest that paternal plane of nutrition influences female offspring physiology, particularly at varying growth rates.

6784 A Case of Euthyroid Hyperthyroxinemia due to Thyroid Binding Globulin Excess Syndrome

Abstract Disclosure: A.S. Iyer: None. Background: Congenital thyroid binding globulin (TBG) excess is a rare phenomenon associated with elevated serum total T3 and total T4 concentrations but normal serum concentrations of free thyroid hormones, with clinically euthyroid patients. While TBG excess can be caused by pregnancy, estrogen-secreting tumors, and estrogen therapy, congenital TBG excess follows an X-linked pattern, with hemizygous males most affected, and heterozygous females showing a spectrum of disease due to random inactivation of one X chromosome. Clinical Case: A 39-year-old Caucasian female presented as a referral from the Gastroenterology clinic due to concern for thyroid resistance syndrome. Symptoms included chronic constipation (improving with Miralax®), gradual weight gain of 8 pounds in one year, fatigue, and palpitations. She reported that her total thyroid hormone levels have always been elevated, with other thyroid labs remaining within normal limits, along with family history of similar labs noted in her two sons, father, and paternal grandmother. Upon initial encounter, TSH was 1.637 (0.430-3.550 uIU/mL), total T4 15.4 (4.8-11.7 ug/dL), total T3 231 (80-200 ng/dL), free T4 0.97 (0.70-1.25 ng/dL), free T3 3.2 (1.7-3.7 pg/mL), and albumin 4.2 (3.5-5.0 g/dL). The patient was not on oral contraceptive pills and she denied any pregnancies in the last three years. Thyroid ultrasound showed a normal-appearing homogeneous thyroid gland with a small cyst with colloid and no cervical lymphadenopathy. Initial differential diagnosis included TBG excess syndrome versus familial dysalbuminemic hyperthyroxinemia. Permission was obtained from the patient to access one of her son’s medical records from age 8-weeks old when he was also evaluated for abnormal thyroid labs. TSH was 2.144 (0.350-6.500 uIU/mL), total T4 28.2 (5.0-12.0 ug/dL), free T4 1.55 (0.8-1.8 ng/dL), and free T3 4.0 pg/mL (no reference available). Thyroid binding globulin was found to be elevated at 81 (12-26 mcg/mL) in her son and found to be elevated to 78.0 (13.5-30.9 mcg/mL) in this patient, confirming a diagnosis of TBG excess syndrome. Conclusions: TBG excess syndrome should be considered in the differential of patients with high total T3 and total T4 levels with normal levels of free T3, free T4, and TSH, especially in individuals who have a known family history and who have minimal or nonspecific symptoms. Definitive diagnosis will make further testing and treatment unnecessary. However, if these patients develop hypo- or hyperthyroidism, then use of TSH and free levels of T4 and T3 is necessary to direct management and avoid confusion. Reference: Pappa, T., and S. Refetoff. “Thyroid hormone transport proteins: Thyroxine-binding globulin, transthyretin, and albumin.” Reference Module in Neuroscience and Biobehavioral Psychology, 2017, https://doi.org/10.1016/b978-0-12-809324-5.03494-5. Presentation: 6/2/2024

Can Productive Aptitude and Age Affect Circulating Serotonin, Total Thyroid Hormones, and Cortisol Patterns in Cows?

Cattle productivity, whether in terms of meat yield or milk production, is intricately regulated by a multitude of factors. Among them, hormone concentrations play a significant role, reflecting the complex interplay between endocrine regulation and physiological processes that ultimately determine the efficiency and yield of production. High concentrations of 5-hydroxytriptamine (5-HT) are associated with a reduced metabolic load at the onset of lactation and a lower milk yield. Thyroid hormones (THs) and cortisol also affect several metabolic pathways, including carbohydrate, protein, and lipid metabolism. The aim of this study was to assess if milk or meat aptitudes and age influence circulating 5-HT, THs, and cortisol concentrations, investigating the possible interactions among these parameters. The research was performed on 46 healthy cows of three different breeds. Enzyme-linked immunosorbent assay (ELISA) methods were used to quantify circulating 5-HT and cortisol concentrations, and an immunochemiluminescent analyzer was used for THs. For parameters exhibiting non-normal distributions, an ANCOVA model using age, aptitude, and their interaction as fixed factors was applied. Significant lower T3 concentrations were recorded in dairy cows than in meat cows. Moreover, T4 significantly decreased with advancing age both in cows aimed at milk and meat production. Lastly, T4 was positively correlated with T3 and 5-HT in meat production-oriented cows.

Cross-Sectional Examination of Thyroid Hormones and Environmental Exposure to Multiclass Pesticides in Women of Reproductive Age in China.

Some pesticides have been shown to interfere with thyroid functions through changes in thyroid hormone (TH) levels. However, few human studies have explored associations between TH levels and environmental exposure to currently used pesticides, including neonicotinoids, phenylpyrazoles, phenoxy acids, and azoles. Moreover, such studies often measure biomarkers of exposure in urine or blood, and thus reveal only recent exposure. In contrast, hair has been demonstrated to be a suitable matrix for assessing chronic exposure to both persistent and nonpersistent organic pollutants. We investigated 54 biomarkers of pollutant exposure in relation to tetraiodothyronine (T4), 3,3',5-triiodothyronine (T3), 3,3',5'-triiodothyronine (rT3), and 3,3'-diiodothyronine (T2). In a cross-sectional study of 196 healthy Chinese women of reproductive age (25-45 years of age), concentrations of both pollutants and THs were analyzed in the first (starting from the scalp) of the hair matrix, collected in 2016. Associations between pollutants and TH levels were explored using stability-enhanced least absolute shrinkage and selection operator (lasso) by regressing all exposures against each outcome of interest, adjusted for age, body mass index, and city. Each TH was associated with the mixture of at least eight of the examined pesticides. We found associations of -HCH, PCP, DMP, DETP, 3Me4NP, carbofuran, , imidacloprid, 2,4-D, metolachlor, difenoconazole, and tebuconazole with THs. For example, a 2-standard deviation (SD) increase in -transformed hair DMP concentration was associated with lower hair T4 concentration [ (95% CI: , )] and higher hair T3 concentration [8.16% (95% CI: 1.73, 15.0%)] in the adjusted unpenalized regression models. We also found associations of some pesticides with T3/T4, rT3/T4, and rT3/T3 molar ratios, including PCP, DMP, 2,4-D, metolachlor, difenoconazole, and tebuconazole. Our results suggest that exposure to the low levels of pesticides examined here may disrupt thyroid homeostasis in humans. Further studies are needed to confirm our results and to evaluate the long-term consequences of these subtle interferences. https://doi.org/10.1289/EHP14378.

A Physiological Study of the Effect of Bee Pollen on Albino Rats Induced Hypothyroidism

The current study aimed to evaluate the therapeutic role of bee pollen (BP) in reducing the harmful effects resulting from hypothyroidism compared to the drug thyroxine on some physiological indicators and improving their levels, which included weight gain (gm), hormone level (T3, T4, TSH), level TPO, cholesterol levels, HDL, LDL, VLDL, and liver enzymes ALT, AST, Hypothyroidism was induced in (24) male rats using the drug carbimazole (CBZ) Which lasted for (15) days at 30 mg/kg of body weight. A random sample was chosen to confirm the occurrence of hypothyroidism, as the results of examining blood samples that were drawn from the animals showed a high concentration of the TSH hormone and Low concentrations of thyroid hormones in the serum compared to the negative control., and this indicates the occurrence of hypothyroidism. Then the animals in which hypothyroidism was induced were separated into 3 experimental collections in addition to the control group and a fifth group. Each group consists of (8) animals. The dosing period lasted thirty days orally. The negative control group, G1, was provided with a diet and water freely. G2 was continued to be dosed with the drug (CBZ) at a concentration of 30 mg/kg of body weight. G3 was continued to be dosed with the drug (CBZ) at a concentration of 30 mg/kg and solution (BP). At a concentration of 200 mg/kg body weight, G4 was dosed with levothyroxine at a concentration of 20 mg/kg body weight, while G5 was dosed with BP solution only at a concentration of 200 mg/kg body weight. At the end of the experiment, the animals were sacrificed and blood samples were obtained. The results were less than 0.05 in group G2 in body weight, the concentration of thyroid hormones T3 and T4, and the concentration of TPO and HDL, and a significant increase (P&lt;0.05) in the concentration of TSH, Cholesterol, LDL, and VLDL, respectively, with an increase in the concentration of liver enzymes. AST and ALT compared to the control group. As for the G3 and G4 groups, the result appeared an original increase a total body weight and the concentration of the hormones T3, T4, and the TPO enzyme, a noticeable improvement in the lipid profile, and a low level of the ALT enzyme and the and thyroid-stimulating hormone compared to the G2 group. As for the group G5 has witnessed an increase in T4 concentration and a decrease in ALT concentration and body weight, and the concentrations of T3, TSH, and TPO are closer to control. We conclude from the current study that BP has a role in reducing the effects of hypothyroidism, increasing weight gain, and improving the lipid profile and the level of ALT liver enzymes. AST and Thyroid peroxidase (TPO) level.

Combined Levothyroxine and Propylthiouracil Treatment in Children with Monocarboxylate Transporter 8 Deficiency: A Multicenter Case Series of 12 Patients.

Objective: To evaluate the combined administration of propylthiouracil (PTU) and levothyroxine (LT4) in managing monocarboxylate transporter 8 (MCT8) deficiency and identify optimal therapeutic dosages. Methods: This multicenter case series involved 12 male patients with MCT8 deficiency whose parents/guardians consented to PTU and LT4 treatment. Data were collected from January 2008 to June 24, 2024. The study focused on treatment safety and outcomes, analyzing baseline and last encounter biochemical, metabolic, and anthropometric parameters. Statistical analyses included Wilcoxon signed ranks tests and generalized estimated equations to assess effects on thyroid and metabolic markers, and receiver operating characteristics curves to predict optimal dose. Results: Patients showed a significant reduction in serum total triiodothyronine (TT3) concentration and TT3/TT4 ratio, with increased serum TT4 and free T4 (fT4) concentrations. The use of PTU effectively reduced TT3 concentration by 25% at an average dose of 6.8 mg/kg/day, while LT4 increased fT4 concentration by 40% from baseline at an average dose of 4.3 µg/kg/day. Thyrotropin concentration was undetectable on treatment. No statistical differences were observed in metabolic and physical parameters between baseline and last encounter overall for the group, but six of eight patients for whom these data were available had an increase in weight (z-score). There were no adverse effects on liver function or granulocyte numbers noted throughout the period of observation. Conclusion: Combined treatment with PTU and LT4 normalized serum T3, fT4, and TT4 in patients with MCT8 deficiency. Individualized dose adjustments were crucial for achieving therapeutic goals, indicating the need for personalized treatment plans.

Alleviating Effects of Methyl Jasmonate on Pepper (Capsicum annuum L.) Seedlings under Low-Temperature Combined with Low-Light Stress.

Low temperature combined with low light (LL) is an important factor limiting pepper quality and yield. 'Hang Jiao No. 2' were used as experimental materials, and different concentrations of MeJA (T1 (0 μM), T2 (100 μM), T3 (150 μM), T4 (200 μM), T5 (250 μM) and T6 (300 μM)) were sprayed under LL stress to explore the positive effect of exogenous methyl jasmonate (MeJA) on peppers under LL stress. The photosynthetic properties, osmoregulatory substance, reactive oxygen species, antioxidant enzyme activities, and related gene expressions of the peppers were measured. Our results demonstrated that 200 μM MeJA treatment significantly increased chlorophyll content, light quantum flux per active RC electron transfer (Eto/RC), maximum captured photonic flux per active RC (TRo/RC), energy flux for electron transfer in the excitation cross section (Eto/CSm), energy flux captured by absorption in the excitation cross section (TRo/CSm), soluble protein, and soluble sugar content. Moreover, it significantly improved the maximum photochemical efficiency of PSII (Fv/Fm) and performance index based on absorbed light energy (PI (abs)) by 56.77% and 67.00%, respectively, and significantly decreased malondialdehyde (MDA) content and relative conductivity by 30.55% and 28.17%, respectively. Additionally, antioxidant enzyme activities were elevated, and the expression of the related genes was activated in pepper seedlings under stress, leading to a significant reduction in reactive oxygen species content. In conclusion, our findings confirmed that 200 μM MeJA could reduce the injury of LL to pepper leaves to the photosynthetic organs of pepper leaves, protect the integrity of the cell membrane, and further improve the tolerance of pepper seedlings to LL.

Disturbed function of TBL1X has a differential effect on T3-regulated gene expression in two human liver cell models.

Mutations in TBL1X, part of the NCOR1/SMRT corepressor complex, were identified in patients with hereditary X-linked central congenital hypothyroidism and associated hearing loss. The role of TBL1X in thyroid hormone (TH) action, however, is incompletely understood. The aim of the present study was to investigate the role of TBL1X on T3-regulated gene expression in two human liver cell models. A human hepatoma cell line (HepG2) wherein TBL1X was downregulated using siRNAs, and human-induced pluripotent stem cell-derived hepatocytes (iHeps) generated from individuals with a TBL1X N365Y mutation. Both cell types were treated with increasing concentrations of T3. The expression of T3-regulated genes was measured by qPCR. KLF9, CPT1A, and PCK1 mRNA expression were higher upon T3 stimulation in the HepG2 cells with decreased TBL1X expression compared to controls, while DIO1 mRNA expression was lower. Hemizygous TBL1X N365Y iHeps exhibited decreased expression of CPT1A, G6PC1, PCK1, FBP1, and ELOVL2 compared to cells with the heterozygous TBL1X N365Y allele, but KLF9 and HMGCS2 expression was unaltered. Downregulation of TBL1X in HepG2 cells and the TBL1X N365Y variant in iHeps have differential effects on T3-regulated gene expression. This suggests that TBL1X may play a gene context role in TH action.

PSI-24 Acute and chronic stress response following weaning and transportation in the average piglet

Abstract The American swine industry relies on a model where facilities for farrowing are often geographically isolated from those used later for wean-finish, which necessitates multiple coincident stressors including weaning, mixing, transportation and feed/water restriction. Previous studies indicate this combined stress reduces subsequent growth performance; however, the specific impact of each stressor on an average, objectively healthy piglet is not well understood, nor is the acute physiological response to this life event. The objective of this study was to determine the effect these stressors on thyroid function, intestinal health, and body weight (BW) in average, healthy pigs. In this study, a total population of 588 piglets were weighed the day prior to weaning and 230 piglets with the lowest Z-scores for BW were selected (5.74 ± 0.70 kg). Piglets (n = 70) were weaned directly into nursery pens and provided with feed and water, 70 were transported for 10 h with no access to feed and water, and 70 were grouped together into 2 large pens with no access to feed and water for an equivalent 8 h period. The remaining 20 piglets were not weaned and served as an unstressed control group. A total of 10 pigs from each group were euthanized at 32 and 56 h post-weaning for tissue sampling. Ileal villi height, crypt depth, and goblet cell numbers were measured, and no treatment effects observed (P &amp;gt; 0.05). Serum triiodothyronine (T3) concentrations were measured pre-treatment (t = 0), 24 h (t = 24), 48 h (t = 48), and immediately following euthanasia (t = 32 or 56 d). There were no significant differences in serum T3 among treatments at t = 0. At all-time points post stress event, control piglets had greater T3 concentrations compared with feed restricted (P &amp;lt; 0.05) and transported (P &amp;lt; 0.05) pigs. Weaned pigs at t = 32, t = 48, and t = 56 had decreased T3 concentrations (P &amp;lt; 0.05) and weaned pigs tended (P = 0.0584) to have decreased t = 24 T3 concentrations compared with pigs remaining with the sow. The remaining pigs (n = 50) per weaning group were weighed weekly throughout the nursery phase and every 3 wk in the grow-finish phase to determine the impact of each stressor on growth. There was no significant effect of weaning treatment on BW at any time point (P &amp;gt; 0.10). Carcass data including carcass weight, loin and backfat depths, and lean percentage were measured at time of slaughter with no significant differences found among groups (P &amp;gt; 0.60). As no effect on growth weight or carcass characteristics were observed between treatment groups in average pigs, this suggests that it may be beneficial to transport average pigs the longest distance, while minimizing transport for pigs on either end of the weaning weight spectrum. Further research is needed to compare effects of weaning and transportation stressors on average and weight extremes of weaned pigs.

105 Fetal hypothyroidism dysregulates local hepatic and renal renin-angiotensin systems in a temporal manner

Abstract The renin-angiotensin system (RAS) is an essential endocrine system with roles in electrolyte balance, blood volume, and blood pressure. While the canonical RAS exerts systemic vasoregulatory effects through steps involving hepatic, renal, and pulmonary-derived compounds, there is also evidence of localized, independently acting RAS in organs such as the liver and kidney. Further, modulations in RAS resulting from fetal hypothyroidism have previously been documented, although the temporal specificity of this endocrine interaction is not well-characterized. Thus, the objective of the current study was to examine the time-dependency of modulations in local hepatic and renal RAS in a porcine model of fetal hypothyroidism. To achieve this, pregnant gilts (n = 24) were divided evenly into either a control (CON) or methimazole (MMI) treatment group, with the MMI group receiving 5 mgּ kg-1ּ d-1 of oral MMI treatment and the CON group receiving an equivalent sham carrier. Each group was further divided into four timepoints (n = 3/treatment at each timepoint), with treatment beginning on d 34, 45, 55, or 65 of gestation. After 21 d of treatment, and at d 55, 66, 76, and 86, respectively, the gilts were humanely euthanized, blood samples taken from all fetuses (n = 340), and thyroid, liver (LVR), and kidney (KID) collected from a subset of four fetuses per litter (n = 96). Confirmation of fetal hypothyroidism in the MMI group was accomplished via histological assessment of the thyroid and measurement of circulating thyroxine (T4) concentrations. Each MMI-treated fetus (n = 96) subset showed evidence of goitrous thyroid histology, with the absence of healthy eosinophilic colloid indicating successful disruption of the fetal hypothalamic-pituitary-thyroid axis. T4 assays performed on a similar subset of n = 96 fetuses showed that MMI treatment significantly reduced T4 concentrations within each timepoint relative to CON (P &amp;lt; 0.001 at all timepoints). Following confirmation of hypothyroidism, RNA was extracted from the fetal LVR and KID samples to allow for gene expression analysis by qPCR. Ct values were normalized, fold changes calculated using the 2-∆∆Ct method, and differences within timepoint determined using a Wilcoxon signed-rank test. AGT, the precursor to all bioactive RAS peptides, was significantly downregulated in LVR at d 66 (P = 0.014) and 76 (P &amp;lt; 0.001). ACE was significantly upregulated at d 76 in both LVR (P = 0.037) and KID (P = 0.005). No significant changes were observed for ACE2 in either tissue, or for renal REN. Finally, AGTR1, the receptor that mediates RAS effects, was significantly downregulated at d 55 in KID (P &amp;lt; 0.001) and d 76 in LVR (P = 0.023), while also being upregulated at d 86 in LVR (P = 0.033). Collectively, these results show that fetal hypothyroidism modulates RAS function in a gestational age-dependent manner, which may alter fetal development and subsequent postnatal physiology.

Advancing plant-based meat analogs: Composite blend of pulse protein reinforcing structure with fibrous mushroom, jackfruit seed powder and carboxymethyl cellulose.

In this study, Indian pulse proteins from cowpeas, yellow peas, green gram, and horse gram were used to create plant-based meatball analogs. The nutritional composition, molecular functional groups, color, and texture of meatball analogs T1, T2, and T3 and mutton meatballs were thoroughly analyzed. T1 had highest protein (51%) compared to control (19%), T2 (45%), and T3 (36%), but fiber content (1.26%) was less in T1 compared to control (2.86%), T2 (3.33%), and T3 (3.49%). The more is fibrous raw materials; lower will be the hardness of meat analogs. T1 had consistent fracturability, hardness, cohesiveness, and adhesiveness, and was superior in springiness, gumminess, resilience, and chewiness compared to T2, T3, and control. Sensory evaluation results reported that T1 was more consistent with control sample in terms of color, texture, juiciness, and overall acceptability and no significant difference was reported among the two (p > .05). The L* and b* values of T1 were more consistent with control compared to other two. Potato starch, salt, spice mix, coriander leaves, beet root pulp, jackfruit seed powder, rose water, carboxy methyl cellulose and rehydrated mushrooms showed a positive impact on sensory and textural attributes. The Fourier transform infrared (FTIR) spectra revealed that the protein fractions were not affected by the processing conditions. FTIR results confirm the presence of secondary structural components such as α-helix, β-sheet, and β-turn. The interaction between the starchy fibrous material and protein fractions were identified clearly via FTIR. The T1 meat analog was superior in terms of color, organoleptic and textural properties compared to T2 and T3 and more close to mutton meatballs. These results will open up the new horizons in this area and pave the way for the large production and marketing of plant based meat analogs, which will reduces the health and sustainable raising issues from consumption of mutton meat.

Embryonic thermal manipulation and post-hatch dietary guanidinoacetic acid supplementation alleviated chronic heat stress impact on broiler chickens

The study investigated the effects of embryonic thermal manipulation (TM) and post-hatch guanidinoacetic acid (GAA) supplementation on male broiler chickens exposed to chronic heat stress (HS). Ross 308 eggs (n = 710) were randomly assigned to control (37.8 °C, 56% RH) or TM (39.5 °C, 65% RH for 12 h/day from embryonic day 7–16) treatments. After hatching, chicks were further assigned to four dietary treatments (n = 12 birds/pen, 5 replicates/treatment): control, control with 1.2 g/kg GAA supplementation (CS), TM, and TM with 1.2 g/kg GAA supplementation (TMS). All birds were subjected to chronic HS (32–36 °C and 55% RH for 6 h/day) from day 28–42. Embryonic TM treatment decreased hatchability, hatching weight (HW), and facial temperature (FT). During the pre-HS period (days 1–28), no significant differences in feed conversion ratio (FCR) and mortality were observed, although the TM group exhibited the lowest body weight gain (BWG). Following HS exposure (days 29–42), the TMS group displayed significantly higher BWG than the control and CS groups. The TM and TMS groups also demonstrated significantly lower FCR and mortality rates during this period. Across the entire period (days 1–42), BWG was significantly higher in the TMS group compared to other groups. Furthermore, TM and TMS treatments were associated with lower mortality rates, improved FCR, better European Performance Efficiency Index (EPEI), and reduced abdominal fat deposition. The experimental treatments did not significantly affect intestinal morphology or most blood parameters, except triiodothyronine (T3), thyroxine (T4), and uric acid. Plasma concentrations of T3, T4, and uric acid were significantly lower in the TM and TMS groups compared to the control and CS treatments. The findings suggest that a combined strategy of embryonic TM and post-hatch dietary GAA supplementation may not only alleviate the detrimental effects of HS but also promote beneficial physiological responses in broiler chickens.

Revisiting the hormonal control of sexual dimorphism in chicken feathers

Sexual dimorphism in plumage is widespread among avian species. In chickens, adult females exhibit countershading, characterized by dull-colored round feathers lacking fringe on the saddle, while adult males display vibrant plumage with deeply fringed bright feathers. This dimorphism is estrogen-dependent, and administering estrogen to males transforms their showy plumage into cryptic female-like plumage. Extensive studies have shown that estrogen’s role in female plumage formation requires thyroid hormone; however, the precise mechanisms of their interaction remain unclear. In this study, we investigated the roles of estrogen and thyroid hormone in creating sexual dimorphism in the structure and coloration of saddle feathers by administering each hormone to adult males and observing the resulting changes in regenerated feathers induced by plucking. RT-PCR analysis revealed that the expression of type 3 deiodinase (DIO3), responsible for thyroid hormone inactivation, correlates with fringing. Estrogen suppressed DIO3 and agouti signaling protein (ASIP) expression while stimulating BlSK1, a marker of barbule cells, resulting in female-like feathers with mottled patterns and lacking fringes. Administration of thyroxine (T4) stimulated BlSK1 and proopiomelanocortin (POMC) expression, with no effect on ASIP, leading to the formation of solid black feathers lacking fringes. Triiodothyronine (T3) significantly increased POMC expression in pulp cells in culture. Taken together, these findings suggest that estrogen promotes the formation of solid vanes by suppressing DIO3 expression, while also inducing the formation of mottled patterns through inhibition of ASIP expression and indirect stimulation of melanocortin expression via changes in local T3 concentration. This is the first report describing molecular mechanism underlying hormonal crosstalk in creating sexual dimorphism in feathers.

Features of the functioning of the hypothalamic-pituitary-thyroid axis in mice with Lewis carcinoma on the background of induced hyperthyroidism

Thyroid hormones (TH) influence the processes of cell proliferation and differentiation, but their role in the processes of carcinogenesis is contradictory. The purpose of the study. To study the effect of induced hyperthyroidism in mice of both sexes with intertwined Lewis carcinoma (LLC) on the activity of the hypothalamic-pituitary-thyroid axis (GGT). Materials and methods. The experimental model was mixed-sex mice of the C57BL/6 line with subcutaneously transplanted LLC on the background of induced hyperthyroidism (main group). Two control groups were used: control group I – mice with sodium liothyronine- induced hyperthyroidism and control group II – mice with subcutaneously transplanted LLC. On the 25th day after tumor transplantation, the level of thyrotropin- releasing hormone (TRH), thyroid- stimulating hormone (TSH), triiodothyronine (T3), total and free thyroxine (T4, FT4) was determined in the homogenates of GGT organs and in blood serum. Results. In female mice, hyperthyroidism caused an increase in the level of TRH in the hypothalamus and a decrease in TSH in the pituitary gland; in males, a decrease in TRH only in the hypothalamus. In control group II, euthyroid disorder syndrome developed: In mice of both sexes, serum levels of T4 and FT4 were found to decrease against the background of unchanged T3 levels and an increase in TSH content only in females. In the females of the main group, an increase in the level of TSH in the thyroid gland caused a decrease in T3 content in 73 % of animals against the background of normal T4 and elevated FT4 levels, in 27 % of females the T3 level increased. In males, in 73 % of the observations, the T3 level was increased against the background of high T4 and FT4 values and unchanged TSH levels. In the skin and LLC samples of the mice of the main group, an increase in T3 levels was noted. Conclusion. The growth of LLC against the background of hyperthyroidism is a process with multifactorial effects. High levels of T3 in blood serum and skin stimulated the proliferation of tumor cells, which led to the formation of subcutaneous tumors of a larger volume in the mice of the main group. Sex differences in the GGT response indicate different mechanisms that implement pathological processes.