Kisspeptin-10 Improves Testicular Redox Status but Does Not Alter the Unfolded Protein Response (UPR) That Is Downregulated by Hypothyroidism in a Rat Model.

Hypothyroidism compromises the testicular redox status and is associated with reduced sperm quality and infertility in men. In this regard, studies have demonstrated the antioxidant potential of kisspeptin in reproductive and metabolic diseases. In this study, we evaluate the effects of kisspeptin-10 (Kp10) on the testicular redox, as well as mediators of the unfolded protein response (UPR) in adult rats with hypothyroidism. Adult male Wistar rats were randomly separated into the Control (n = 15), Hypo (n = 13) and Hypo + Kp10 (n = 14) groups, and hypothyroidism was induced with 6-propyl-2-thiouracil (PTU) for three months. In the last month, half of the hypothyroid animals received Kp10. Testis samples were collected for enzymatic, immunohistochemical and/or gene evaluation of mediators of oxidative stress (TBARs, lipid hydroperoxides (LOOH), ROS, peroxynitrite, SOD, CAT and GPX), endoplasmic reticulum stress (GRP78, ATF6, PERK, CHOP, HO-1 and sXBP1) and antiapoptocytes (BCL-2). Hypothyroidism increased apoptosis index, TBARS and LOOH concentrations, and reduced testicular gene expression of Sod1, Sod2 and Gpx1, as well as the expression of Grp78, Atf6, Ho1 and Chop. Treatment with Kp10, in turn, reduced testicular apoptosis and the production of peroxynitrite, while increased SOD1 and GPX ½ expression, and enzymatic activity of CAT, but did not affect the lower expression of UPR mediators caused by hypothyroidism. This study demonstrated that hypothyroidism causes oxidative stress and dysregulated the UPR pathway in rat testes and that, although Kp10 does not influence the low expression of UPR mediators, it improves the testicular redox status, configuring it as an important antioxidant factor in situations of thyroid dysfunction.

Pyometra and estrous cycle modulate the uterine expression of the kisspeptin system and angiogenic and immune factors in cats.

Failures in hypothalamic kisspeptin/Kiss1r signaling are associated with infertility, and in vitro studies have shown that kisspeptin can modulate angiogenesis and immune activity. Because there is no in vivo research on the functional relationship between these factors in the reproductive system, especially in domestic cats, we evaluated the expression profile of kisspeptin/Kiss1r and angiogenic and immunological mediators in the genital tract of cyclic cats and of those with pyometra. The uterus of cats in diestrus exhibited greater gene and protein expression of Kiss1, as well as Vegf, Pigf, Mif, and Il6. In contrast, Kiss1r presented greater expression in proestrus/estrus, similarly to that observed for the immunostaining of INFγ, MIF, TNFα, and IL10. These factors were positively correlated with Kiss1 and/or Kiss1r, and a positive correlation between Kiss1 and Kiss1r was also observed in the uterus of cats during the estrous cycle. Cats with pyometra showed greater immunostaining of Kiss1 and Kiss1r on the endometrial surface and reduced immunostaining of Kiss1 in deep glands, whereas there was a significant reduction in Vegf, Pigf, Mif, and Il6 mRNA, and an increase in Tnf mRNA. The findings reveal that there is a gene correlation between kisspeptin/Kiss1r and angiogenic and immune mediators in the uterus of the domestic cat, which is modulated by the estrous cycle, and that pyometra affects the expression of these mediators. This study suggests, for the first time, a functional relationship between the Kiss/Kiss1r system and angiogenic and immune mediators in the female genital tract.

Kisspeptin/Kiss1r system and angiogenic and immunological mediators at the maternal-fetal interface of domestic cats.

The Kisspeptin/Kiss1r system is a key regulator of reproduction by stimulating gonadotrophin-releasing hormone and luteinizing hormone release, and in vitro studies have shown that Kisspeptin can modulate angiogenesis and immune function, factors that are also essential for reproduction However, there are no studies on the expression of Kisspeptin/Kiss1r at the maternal-fetal interface in domestic cats and its relationship with angiogenic and immunological mediators. Thus, our objective was to evaluate the spatiotemporal expression profile of Kisspeptin/Kiss1r and angiogenic and immunological mediators in the uterus and placenta of domestic cats during pregnancy. Uterus and placenta samples were collected from cats in mid pregnancy (N = 6) and late pregnancy (N = 6), in addition to uterus from non-pregnant cats in diestrus (N = 7), to evaluate protein and gene expression of kisspeptin (Kiss1), kisspeptin receptor (Kiss1r), vascular endothelial growth factor (VEGF), tyrosine kinase receptor (Flk-1), placental growth factor (PLGF), interferon gamma (INFγ), migration inhibiting factor (MIF), tumor necrosis factor (TNFα), interleukins (IL6 and IL10) by immunohistochemistry and quantitative polymerase chain reaction. Pregnancy increased the uterine expression of Kiss1 and Kiss1r, especially at the late pregnancy, in addition to upregulating INFy, MIF, Vegf, Il10, and Tnf and downregulating Plgf. Higher placental expression of Kiss1r and Plgf mRNA occurred at the late pregnancy, while the expression of Kiss1, VEGF, Flk-1, INFy, TNFα, Il6, and IL10 was higher in the mid of pregnancy. A positive correlation between Kiss1 and Tnf was observed in the placenta, while Kiss1r had a negative correlation with Infγ, Il6, and Il10. The findings reveal that Kisspeptin/Kiss1r and angiogenic and immunological mediators at the maternal-fetal interface of pregnant cat have a gene correlation and are modulated by the gestational age. These data suggest possible functional links of Kisspeptin in placental angiogenesis and immunology.

The Solanum glaucophyllum Desf. extract reduces mineralized matrix synthesis in osteogenically differentiated rat mesenchymal stem cells in vitro.

The Solanum glaucophyllum Desf. has been used to treat and prevent diseases in human and veterinary medicine. On the other hand, plant poisoning causes several bone diseases, among them osteoporosis, which is characterized by osteoblastic hypoplasia. Because the osteoblast is a cell derived from the differentiation of mesenchymal stem cells (MSCs) from bone marrow, the hypothesis is that the plant reduces the osteogenic differentiation of MSCs. The objective of this study was to evaluate the effects of S. glaucophyllum Desf. extract on MSCs cultured in osteogenic differentiation medium. We determined by liquid chromatography that 1 ml of plant extract contained 3.8 µl of 1,25(OH)2 D3 (calcitriol). Four groups of MSCs cultivated in osteogenic medium were evaluated as follows: (a) treated with 100 µl of extract/L containing 0.4 µg/L of calcitriol; (b) treated with 1 ml of extract/L containing 4 µg/L of calcitriol; (c) treated with 5 ml of extract/L containing 20 µg/L of calcitriol; and (d) a control group without extract. We performed alkaline phosphatase activity assay, analysis of MTT conversion to formazan, and evaluated the percentage of cells, and number and diameter of mineralization nodules. The expression of gene transcripts for osteopontin, bone sialoprotein and BMP-2 was analysed by RT-qPCR. After 21 days, there was a significant reduction in MTT conversion to formazan in treated groups, of the cellularity in the group with 5 ml of extract/L, and in the number and size of mineralization nodules in the groups treated with 1 and 5 ml of extract/L. The 5 ml extract/L concentration also reduced transcript expression of osteopontin. It is concluded that S. glaucophyllum Desf. at concentrations of 1 and 5 ml extract/L reduced mineralized matrix synthesis in MSCs cultivated in osteogenic differentiation medium, which suggests that this is one of the mechanisms by which osteoporosis occurs in intoxicated animals.

Thyroid hormones and female reproduction.

Thyroid hormones are vital for the proper functioning of the female reproductive system, since they modulate the metabolism and development of ovarian, uterine, and placental tissues. Therefore, hypo- and hyperthyroidism may result in subfertility or infertility in both women and animals. Other well-documented sequelae of maternal thyroid dysfunctions include menstrual/estral irregularity, anovulation, abortion, preterm delivery, preeclampsia, intrauterine growth restriction, postpartum thyroiditis, and mental retardation in children. Several studies have been carried out involving prospective and retrospective studies of women with thyroid dysfunction, as well as in vivo and in vitro assays of hypo- and hyperthyroidism using experimental animal models and/or ovarian, uterine, and placental cell culture. These studies have sought to elucidate the mechanisms by which thyroid hormones influence reproduction to better understand the physiology of the reproductive system and to provide better therapeutic tools for reproductive dysfunctions that originate from thyroid dysfunctions. Therefore, this review aims to summarize and update the available information related to the role of thyroid hormones in the morphophysiology of the ovary, uterus, and placenta in women and animals and the effects of hypo- and hyperthyroidism on the female reproductive system.

Excess maternal and postnatal thyroxine alters chondrocyte numbers and the composition of the extracellular matrix of growth cartilage in rats.

Purpose/Aim: The aim of this study was to evaluate the effects of excess maternal and postnatal thyroxine on chondrocytes and the extracellular matrix (ECM) of growth cartilage. MATERIALS AND METHODS: We used 16 adult female Wistar rats divided into two groups: thyroxine treatment and control. From weaning to 40 days of age, offspring of the treated group (n = 8) received L-thyroxine. Plasma free T4 was measured. Histomorphometric analysis was performed on thyroids and femurs of all offspring. Alcian blue histochemical staining and real-time reverse transcription polymerase chain reaction measurements of gene expression levels of Sox9, Runx2, Aggrecan, Col I, Col II, Alkaline phosphatase, Mmp2, Mmp9, and Bmp2 were performed. Data were analyzed for statistical significance by student's t-test. RESULTS: Excess maternal and postnatal thyroxine reduced the intensity of Alcian blue staining, altered the number of chondrocytes in proliferative and hypertrophic zones in growth cartilage, and reduced the gene expression of Sox9, Mmp2, Mmp9, Col II, and Bmp2 in the growth cartilage of all offspring. Additionally, excess thyroxine altered the gene expression of Runx2, Aggrecan and Col I, and this effect was dependent on age. CONCLUSIONS: Excess thyroxine in neonates suppresses chondrocyte proliferation, stimulates chondrocyte hypertrophy and changes the ECM composition by reducing the amount of proteoglycans and glycosaminoglycans (GAGs). Prolonged exposure to excess thyroxine suppresses chondrocyte activity in general, with a severe reduction in the proteoglycan content of cartilage and the expression of gene transcripts essential for endochondral growth and characteristics of the chondrocyte phenotype.

Spatiotemporal expression profile of proteases and immunological, angiogenic, hormonal and apoptotic mediators in rat placenta before and during intrauterine trophoblast migration.

The gene and/or protein expression of proteases and immunological, angiogenic, hormonal and apoptotic mediators was evaluated in rat placenta before and during intrauterine trophoblast migration. The depth of interstitial and endovascular intrauterine trophoblast invasion and the immunohistochemical expression of vascular endothelial growth factor (VEGF), fetal liver kinase 1 (Flk1), interferon (IFN)-γ, migration inhibitory factor (MIF), and inducible nitric oxide synthase (iNOS; also known as nitric oxide synthase (NOS) 2) were evaluated. In addition, the expression of the Vegf, Flk1, placental growth factor (Pigf), soluble fms-like tyrosine kinase 1 (sFlt1), placental lactogen 1 (Pl1), proliferin-related protein (rPlf), placental leptin (Lep), Toll-like receptor 2 (Tlr2), Toll-like receptor 4 (Tlr4), Infg, Mif, tumour necrosis factor-α (Tnf), interleukin-10 (Il10), Nos2, caspase 3 (Casp3), Bax, Bcl2, matrix metalloproteinase 2 (Mmp2) and matrix metalloproteinase 9 (Mmp9) genes was determined by real-time reverse transcription-polymerase chain reaction. At 10 days gestation, gene expression of Tlr2, Tlr4, Tnf, Infg, Il10, Casp3, Pigf, sFlt1 and Lep (P<0.05) were higher than at 14 and/or 19 days of gestation. The beginning of intrauterine trophoblast invasion, i.e., at 14 days of gestation, coincided with higher gene and/or protein expression of MMP9, VEGF, Flk1, NOS2, MIF, BAX and rPlf compared to days 10 and 19 (P<0.05). In contrast, gene expression of Mmp2 and Pl1 was higher at the end of trophoblast invasion compared to 10 and 14 days of gestation (P<0.05). In conclusion, before intrauterine trophoblast migration, expression of TLRs and immunological and pro-apoptotic mediators is higher, whereas the beginning of trophoblast migration is characterised by higher expression of the pro-angiogenic factors NOS2 and MMP9. In contrast, MMP2 and PL1 expression is higher at the end of intrauterine trophoblast migration.

Inhibition of the osteogenic differentiation of mesenchymal stem cells derived from the offspring of rats treated with caffeine during pregnancy and lactation.

Caffeine is an alkaloid that is widely consumed due to its presence in drugs, coffee, tea, and chocolate. This compound passes to offspring through the placenta and milk; can cause teratogenic mutations; and reduces the formation, growth, and mass of bone. Because mesenchymal stem cells (MSCs) are responsible for generating the entire skeleton, we hypothesized that these cells are targets of caffeine. This study evaluated the osteogenic differentiation of MSCs derived from the offspring of rats treated with caffeine during pregnancy and lactation. Twenty-four adult Wistar rats were randomly divided into four groups, including one control group and three experimental groups treated with 25, 50, or 100 mg/kg of caffeine. At weaning, three 21-day-old pups from each dam in each group were euthanized for extraction of bone marrow cells for in vitro tests. Caffeine doses of 50 and 100 mg/kg significantly reduced the activity of alkaline phosphatase at 7, 14, and 21 days and the expression of collagen I at 21 days. However, the expression of gene transcripts for alkaline phosphatase, Runx-2, and bone sialoprotein, as well as the synthesis of mineralization nodules, decreased significantly in all groups treated with caffeine. The expression of osteocalcin was significantly reduced only in the group treated with 50 mg/kg caffeine. The caffeine that passes from the mother to the offspring during pregnancy and lactation reduces the osteogenic differentiation of MSCs. We propose that this reduction in the osteogenic potential of MSCs may be involved in the pathogenesis of osteopenia resulting from caffeine consumption.

Osteopetrosis in obese female rats is site-specifically inhibited by physical training.

NEW FINDINGS: What is the central question of this study? Clinical studies suggest that obesity 'protects' against osteoporosis. However, these studies used only bone densitometry and assessed only one bone site, which is insufficient to enable conclusions to be drawn about the response of the whole skeleton. Furthermore, the effects of exercise on bone responses in obesity have not been explored previously. What is the main finding and what is its importance? We show that obesity causes osteopetrosis. Therefore, the classical perspective of 'protective effects of obesity' needs to be reviewed, and exercise is an important tool to avoid these alterations and to maintain the homeostasis of bone. A sedentary lifestyle and obesity induce systemic inflammatory responses. Although the effects of physical inactivity on osseous tissue have been well established, the effects of obesity on bone tissue remain controversial. Furthermore, the effects of physical training on bone tissue responses in the presence of diet-induced obesity are unknown. Our aim was to investigate the effects of obesity and physical training at multiple bone sites in rats. Female Wistar rats were divided into the following four groups: (i) control diet, non-trained (C-NT); (ii) high-refined carbohydrate-containing diet, non-trained (HC-NT); (iii) control diet, trained (C-T); and (iv) high-refined carbohydrate-containing diet, trained (HC-T). At 5 months of age, the rats were submitted to daily exercise for 30 min day(-1). After 13 weeks, blood samples, adipose and skeletal tissues were harvested. Two-way ANOVA was applied to detect differences (significance accepted when P ≤ 0.05). The HC-NT group exhibited increased body mass, adiposity, serum leptin, serum insulin, insulin resistance index and concentrations of tumour necrosis factor-α and interleukin-6. Obese rats (HC-NT) exhibited thickening of nasal bones, trabecular bones in the lumbar vertebrae and long bones in a site-dependent manner. The HC-T group exhibited similar adiposity and inflammatory results. Morphological analysis of the lumbar vertebrae in rats fed the HC diet revealed characteristics of osteopetrosis that were inhibited by exercise. In conclusion, the HC diet induced obesity and inflammatory/hormonal alterations and increased the trabecular bone in a site-dependent manner. However, obesity caused osteopetrosis in the lumbar vertebrae, which could be inhibited by physical training. Although exercise inhibited the development of bone alterations, physical training did not inhibit the HC diet-induced obesity responses.

Effect of the ionic product of bioglass 60s on osteoblastic activity in canines.

BACKGROUND: The objective of the present study was to evaluate the effect of the ionic product (IP) of BG60S on osteoblastic activity. The following media groups were created: DMEM, which is formed by osteoblasts in basal medium; IP DMEM, which is formed by osteoblasts in IP with basal medium; OST, which is formed by osteoblasts in osteogenic medium; and IP OST, which is formed by osteoblasts in IP with osteogenic medium. The osteoblasts were cultivated in an incubator at 37 °C and 5 % CO2 for 7, 14 and 21 days. After each period, the alkaline phosphatase (AP) activity, mineralised area per field and expression of osterix (OSX), bone sialoprotein (BSP), osteonectin (ON) and osteocalcin (OC) were evaluated by reverse transcription (RT)-PCR. RESULTS: The IP significantly increased the AP activity in the IP DMEM group at 7 and 14 days and reduced the AP activity in the IP OST group at 14 and 21 days relative to their respective controls (DMEM and OST). The groups that received the IP displayed a significant increase in the percentage of mineralised area per field and more advance maturation of the extracellular matrix relative to those that did not receive IP. The IP significantly increased the expression of OSX, BSP and ON in osteoblast cultures maintained in IP DMEM compared with the control (DMEM) for the majority of studied periods. In osteogenic medium, IP also significantly increased OSX, BSP, ON and OC expression compared with the control (OST) for the majority of studied periods. CONCLUSIONS: The IP of BG60S alters the gene expression of canine osteoblasts, favouring the synthesis and mineralisation of the extracellular matrix.

Osteogenic potential of osteoblasts from neonatal rats born to mothers treated with caffeine throughout pregnancy.

BACKGROUND: Caffeine is an active alkaloid that can cause damage to bones in formation during prenatal life into adulthood. This compound can pass across the placenta and into the mother's milk, causing a reduction in bone formation, growth and mass. The objective of this study was to examine the osteogenic potential of osteoblasts extracted from neonatal rats born to mothers treated with caffeine throughout pregnancy. METHODS: Twenty-four adult Wistar rats were randomly divided into four groups, consisting of one control group and three groups that were treated with 25, 50, or 100 mg/kg of caffeine by an oral-gastric probe throughout the duration of the experimental period (pregnancy). At birth, three puppies from each dam in each group were euthanized, and osteoblasts were extracted from the calvaria of these pups for in vitro testing. RESULTS: The osteoblasts extracted from the pups of rats that received 50 mg/kg caffeine during pregnancy exhibited increased expression of osteocalcin, osteopontin, sialoprotein, runx-2, alkaline phosphatase and type I collagen transcripts, resulting in increased synthesis of mineralization nodules. CONCLUSIONS: Neonates from rats treated with 50 mg/kg caffeine during pregnancy contained osteoblasts with a higher osteogenic potential characterized by increased expression of osteocalcin, osteopontin, sialoprotein, runx-2, alkaline phosphatase and type I collagen and increased synthesis of mineralization nodules.

Maternal thyroid dysfunction affects placental profile of inflammatory mediators and the intrauterine trophoblast migration kinetics.

The objective of the present study was to evaluate the gene and immunohistochemical expression of inflammatory mediators involved in the immune activity and the intrauterine trophoblast migration of the placentas in hypothyroid and L-thyroxine (L-T4)-treated rats. A total of 144 adult female rats were divided equally into hypothyroid, l-T4-treated, and euthyroid (control) groups. Hypothyroidism was induced by daily administration of propylthiouracil. Rats were killed at 0, 10, 14, 15, 16, 17, 18, and 19 days of gestation. We evaluated the depth of interstitial and endovascular intrauterine trophoblast invasion and the immunohistochemical expression of interferon γ (INFy), migration inhibitory factor (MIF), and inducible nitric oxide synthase (NOS2 (iNOS)). The gene expression of Toll-like receptor 2 (Tlr2) and Tlr4, Infy, Mif, tumor necrosis factor (Tnf (Tnfα)), Il10, Nos2, matrix metalloproteinase 2 (Mmp2) and Mmp9, and placental leptin was also measured in placental disks by real-time RT-PCR. The data were analyzed using an Student-Newman-Keuls (SNK) test. Hypothyroidism reduced the endovascular and interstitial trophoblast migration, and the expression of TLR4, INFy, MIF, interleukin 10 (IL10), NOS2, MMP2 and MMP9, and placental leptin, while increased the expression of TLR2 (P<0.05). T4-treated rats not only increased the expression of IL10 and NOS2 but also reduced the expression of TNF and MIF at 10 days of gestation (P<0.05). However, at 19 days of gestation, expression of INFy and MIF was increased in T4-treated group (P<0.05). Excess of T4 also increased the gene expression of Mmp2 at 10 days of gestation (P<0.05), but reduced the endovascular trophoblast migration at 18 days of gestation (P<0.05). Hypothyroidism and excess of T4 differentially affect the immune profile and the intrauterine trophoblast migration of the placenta, and these effects are dependent on the gestational period.

Comparative study of osteogenic differentiation potential of mesenchymal stem cells derived from bone marrow and adipose tissue of osteoporotic female rats.

Osteoporosis causes reduction of osteogenic differentiation of mesenchymal stem cells (MSCs) from bone marrow and adipose tissue. This study was designed to compare the osteogenic potential of bone marrow mesenchymal stem cells (BMMSCs) and adipose-derived stem cells (ADSCs) of ovariectomized (OVX) rats. MSC were harvested from bone marrow and inguinal fat pads of six OVX rats. The limitations of this report are that cells from different animals were pooled for the purpose of the experiments that were carried out in this study. At 7, 14 and 21 d of osteogenic differentiation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) conversion, alkaline phosphatase activity and gene expression for collagen I, osteocalcin, bone sialoprotein, osteopontin and bone morphogenetic protein-2 bone morphogenetic protein-2 (BMP-2) were analyzed. At 21 d, percentage of cells per field and percentage of mineralized nodule were analyzed. The data were subjected to analysis of variance, and the means were compared by Student-Newman-Keuls test. The cells, regardless of group, showed phenotypic characteristics consistent with stem cells. MTT conversion, alkaline phosphatase activity, percentage of mineralized nodule and expression of collagen I, osteocalcin and BMP-2 of ADSCs from OVX rats were higher when compared to BMMSCs from OVX rats in at least one of the evaluated periods (p<0.05). However, bone sialoprotein and osteopontin expression were smaller than those observed in BMMSCs for all evaluated periods (p<0.05). It was concluded that the ADSCs from OVX rats have higher osteogenic potential when compared to BMMSCs from OVX rats. This result suggests that the treatment of osteoporosis with autologous ADSCs may be more efficient.

Comparison of the osteogenic potential of mesenchymal stem cells from the bone marrow and adipose tissue of young dogs.

BACKGROUND: The aim of the present study was to compare the osteogenic potential of mesenchymal stem cells extracted from the bone marrow (BM-MSCs) and adipose tissue (AD-MSCs) of young dogs. The following parameters were assessed: dimethyl thiazolyl diphenyl tetrazolium (MTT) conversion, alkaline phosphatase (ALP) activity, collagen and mineralised matrix synthesis, and the expressions of osterix, bone sialoprotein (BSP), and osteocalcin (OC). RESULTS: MTT conversion was greater in BM-MSCs compared to AD-MSCs after 14 and 21 days of differentiation; ALP activity was greater in differentiated AD-MSCs on day 7; collagen synthesis was greater in BM-MSCs on days 14 and 21; the percentage of mineralized area per field was greater in BM-MSCs compared to AD-MSCs; osterix expression was greater in BM-MSCs in days 14 and 21, and BSP and OC expression levels were greater in BM-MSCs at all the investigation time-points. CONCLUSIONS: It was concluded that the osteogenic potential was greater in BM-MSCs than AD-MSCs when extracted from young dogs.

Bone development in fetuses with intrauterine growth restriction caused by maternal endocrine-metabolic dysfunctions.

Intrauterine growth restriction (IUGR) affects a large proportion of infants, particularly in underdeveloped countries. Among the main causes of IUGR, maternal endocrine-metabolic dysfunction is highlighted, either due to its high incidence or due to the severity of the immediate and mediated changes that these dysfunctions cause in the fetus and the mother. Although the effects of endocrine and metabolic disorders have been widely researched, there are still no reviews that bring together and summarize the effects of these conditions on bone development in cases of IUGR. Therefore, the present literature review was conducted with the aim of discussing bone changes observed in fetuses with IUGR caused by maternal endocrine-metabolic dysfunction. The main endocrine dysfunctions that occur with IUGR include maternal hyperthyroidism, hypothyroidism, and hypoparathyroidism. Diabetes mellitus, hypertensive disorders, and obesity are the most important maternal metabolic dysfunctions that compromise fetal growth. The bone changes reported in the fetus are, for the most part, due to damage to cell proliferation and differentiation, as well as failures in the synthesis and mineralization of the extracellular matrix, which results in shortening and fragility of the bones. Some maternal dysfunctions, such as hyperthyroidism, have been widely studied, whereas conditions such as hypoparathyroidism and gestational hypertensive disorders require further study regarding the mechanisms underlying the development of bone changes. Similarly, there is a gap in the literature regarding changes related to intramembranous ossification, as most published articles only describe changes in endochondral bone formation associated with IUGR. Furthermore, there is a need for more research aimed at elucidating the late postnatal changes that occur in the skeletons of individuals affected by IUGR and their possible relationships with adult diseases, such as osteoarthritis and osteoporosis.

Microscopic Alterations of the Dental Pulp in Surgically Extracted Teeth of Dogs.

Microscopic alterations in the dental pulp of dogs have not been extensively studied. The aim of this study was to investigate microscopic alterations of the dental pulp in dogs' teeth. One hundred and ten surgically extracted teeth (20 incisors, 23 canines, 28 premolars, and 39 molars) from 74 dogs, of different ages, with a history of chronic periodontitis (66 dogs), periapical abscesses (2 dogs), pulpitis (2 dogs), oral cavity neoplasms (2 dogs), dens invaginatus (1 dog), and dental fractures (1 dog) were included. Eight-one maxillary and 29 mandibular teeth were included. Coronal, radicular, and coronal plus radicular calculus were present in 28.2%, 17.3%, and 54.5% of the teeth, respectively. In total 78 teeth (71%) had pulp alterations, including fibrosis (26%), calcification (14%), necrosis associated with the absence of odontoblasts (14%), presence of predentin and dentin inside the cavity (8%), odontoblastic hyperplasia (3%), pigmentation (3%), pulpitis (2%), and pulp stones (1%). Forty-nine (60.5%) of the maxillary teeth and all of the mandibular teeth had pulp alterations. The premolars were most affected, and the molars least affected, by pulp alterations. Pulp fibrosis, calcification, and necrosis were observed in teeth irrespective of the distribution of dental calculus.

Maternal hyperthyroidism alters the immunological mediators profile and population of natural killers cells in decidua of rats.

Decidual immunological mediators modulate placental formation, decidualization and fetal development. However, the effect of maternal hyperthyroidism on decidual immunology needs further research. The aim of this study was to evaluate the population of uterine natural killer cells (uNKs) and the expression of immunological mediators in the decidua of female rats throughout pregnancy. Wistar rats were used and hyperthyroidism was induced by daily administration of L-thyroxine (T4) throughout pregnancy. The population of uNK cells in decidua was evaluated by immunostaining Lectin DBA, as well as the expression of interferon γ (INFγ), macrophage migration inhibitory factor (MIF), interleukin 15 (IL-15) and inducible nitric oxide synthase (iNOS) at 7, 10, 12, 14 and 19 days of gestation (DG). Maternal hyperthyroidism reduced the DBA+ uNK cell population in the decidua at 7 (P < 0.05) and 10 (P < 0.01) DGs compared to that in the control group, while it increased in the basal decidua (P < 0.05) and metrial gland (P < 0.0001) at the 12th DG. Hyperthyroidism also increased immunostaining of IL-15 (P < 0.0001), INFγ (P < 0.05), and MIF (P < 0.05) in the 7th DG, and increased immunostaining of IL-15 (P < 0.0001) and MIF (P < 0.01) in the 10th DG. However, excess thyroxine reduced IL-15 expression in the metrial gland and/or basal decidua in the 12th (P < 0.05), 14th (P < 0.01), and 19th (P < 0.001) DGs, as was also observed for INFγ in the basal decidua (P<0.001) and metrial gland (P < 0.0001) in the 12th DG. Regarding iNOS, an antiinflammatory cytokine, lower expression was observed in the basal decidua of hyperthyroid animals at 7 and 12 DGs (P < 0.05), whereas an increase occurred in the 10th DG (P < 0.05). These data demonstrate that maternal hyperthyroidism in female rats, particularly between 7 and 10 DGs, reduces the population of DBA+ uNKs in the decidua and increases the expression of inflammatory cytokines, suggesting a more proinflammatory environment in early pregnancy caused by this gestational disease.

Effect of the addition of different concentrations of Solanum glaucophyllum desf. extract on chondrocyte cultures from the growth cartilage of newborn rats.

Solanum glaucophyllum Desf. is a calcinogenic plant responsible for enzootic calcinosis that affects ruminants and causes alterations in bone and cartilaginous tissues, among others. It is believed that changes in cartilage tissue, with reduced bone growth, are due to hypercalcitoninism, caused by excess vitamin D. However, we hypothesized that S. glaucophyllum Desf. can act directly on chondrocytes and therefore, chondrocyte cultures from the epiphysis of the long bones of newborn rats were used as a model to elucidate the direct effects of S. glaucophyllum Desf. on bone growth. Plant samples were collected from Cañuelas, Argentina. An aliquot of the plant extract was used to quantify vitamin D (1,25(OH)2D3). The effects of the three concentrations of the plant extract were tested in cultures of chondrocytes extracted from the epiphyses of the long bones of 32 three-day-old Wistar rats. A control group (without extract), and three groups treated with different concentrations of plant extract were formed: group 1 (100 µL/L); group 2 (1 mL/L), and group 3 (5 mL/L), containing respectively 1 × 10-9 M, 1 × 10-8 M, and 5 × 10-8 M of 1,25(OH)2D3. After 7, 14, and 21 days of culture, MTT assay for cell viability, alkaline phosphatase activity, and quantification of the percentage of areas with glycosaminoglycans (GAG) stained with periodic acid-Schiff (PAS) were performed. On day 7, all chondrocytes in group 3, that is, those with the highest concentration of plant extract, died. On days 14 and 21, groups 1 and 2 showed a significant reduction in chondrocyte viability compared to the control. At 7, 14, and 21 days, groups 1 and 2 showed significantly lower alkaline phosphatase activity than the control. On day 21, group 2 showed a significant reduction in areas with PAS + GAGs. There were no significant differences between the groups in the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan. The S. glaucophyllum Desf. extract directly affected growing rat chondrocytes by reducing viability, alkaline phosphatase activity, and GAG synthesis without altering the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan, which may be one of the mechanisms by which there is a reduction in bone growth in animals intoxicated by the plant.

Tracheal stenosis in a yellow-crowned parrot (Amazona ochrocephala) due to diffuse ossification and osteopetrosis of tracheal rings.

Tracheal luminal stenosis can cause clinical respiratory distress in wild birds. We describe a case of tracheal stenosis due to diffuse ossification with osteopetrosis of tracheal rings in a yellow-crowned parrot (Amazona ochrocephala) with a history of chronic respiratory distress and death after development of marked dyspnoea. An ante-mortem radiographic examination revealed that the tracheal rings were radiopaque and that there were multiple areas of osteopenic change in long bones. At necropsy, there was stenosis of the tracheal rings characterized by complete replacement of cartilage by thickened compact bone with osteopetrosis and bone necrosis. The clinical respiratory distress and death of the parrot were associated with tracheal luminal stenosis due to thickening of the tracheal rings by diffuse ossification with osteopetrosis.

Kisspeptin (Kp-10) inhibits in vitro osteogenic differentiation of multipotent mesenchymal stromal cells extracted from the bone marrow of adult rats.

Kisspeptin (Kp-10) is a neuropeptide that binds to GPR54 receptors, exerting several functions mainly in the nervous and reproductive systems of the body. However, its effects and mechanisms of action on the skeletal system remain poorly understood. This study evaluated the effects of different concentrations of Kp-10 on in vitro osteogenic differentiation of multipotent mesenchymal stromal cells (MSCs) extracted from the bone marrow (BM) of adult Wistar rats. Two-month-old female rats were euthanized to extract BM from long bones to obtain MSCs. Four experimental groups were established in vitro: a control and Kp-10 at concentrations of 0.01, 0.05 and, 0.1 µg/mL. After induction of osteogenic differentiation, cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase activity, collagen synthesis, percentage of area covered by MSCs/field and mineralized nodules/field, and immunocytochemistry of the GPR54 receptor tests. Furthermore, evaluation of gene transcripts for type I collagen, Runx-2, Bmp-2, bone sialoprotein, osteocalcin and osteopontin was performed using real-time RT-qPCR. It was observed that MSCs expressed GPR54 receptor to which Kp-10 binds during osteogenic differentiation, promoting a negative effect on osteogenic differentiation. This effect was observed at all the Kp-10 concentrations in a concentration-dependent manner, characterized by a decrease in the activity of alkaline phosphatase, collagen synthesis, mineralized nodules, and decreased expression of gene transcripts for type I collagen, osteocalcin, osteopontin, and Runx-2. Thus, Kp-10 inhibits in vitro osteogenic differentiation of MSCs extracted from the BM of adult Wistar rats.