Superficial versus deep system single venous anastomosis in the radial forearm free flap: a meta-analysis

The selection of the superficial or deep drainage system for use with the radial forearm free flap (RFFF) remains controversial. The aim of this study was to identify the optimal drainage system for single venous anastomosis. A systematic review and cumulative meta-analysis was performed to assess superficial and deep system single venous anastomosis for use with the RFFF in postoperative reconstruction of the head and neck. This study included 1073 flaps (495 superficial system-based flaps, 578 deep system-based flaps) reported in six studies. The outcomes assessed in the studies selected for this meta-analysis included venous compromise, flap failure, and the salvage success rate. Venous compromise was more common in the superficial system group (odds ratio (OR) 2.29, 95% confidence interval (CI) 1.36-3.86, P=0.002). The rate of successful salvage was higher with the superficial system (OR 8.19, 95% CI 1.75-38.3, P=0.008). The rate of flap failure was lower in the superficial system group (OR 0.30, 95% CI 0.04-2.48, P=0.27). Although the deep system showed a lower risk of venous compromise, the evidence provided by the meta-analysis was insufficient to determine which type of drainage system is more suitable for single venous anastomosis in RFFF. All included studies were cohort studies; therefore, findings must be interpreted with caution.

[Transcranial sonographic characteristics of Parkinson's disease with symptoms of restless legs syndrome]

Objective: To evaluate the transcranial sonographic characteristics in patients with Parkinson's disease (PD) with symptoms of restless legs syndrome (RLS). Methods: Patients with diagnosis of definite PD from the Second Affiliated Hospital of Soochow University and 3 other participating hospitals between September 2018 and December 2019 were consecutively enrolled. Concurrent RLS symptoms were determined using Non-motor Symptoms Questionnaire. Transcranial sonography (TCS) and clinical assessments were performed during the same time and the related variables were compared between the two groups using t-test, non-parametric test, Chi-square test and Spearman correlation analysis, respectively. Results: Among 349 patients with PD, the prevalence of RLS symptoms was 22.6%. Compared to patients without RLS symptoms, those with RLS had longer disease duration (43.0 (24.0, 91.0) months vs 37.0 (20.0, 60.0) months, P<0.05) and higher Hoehn-Yahr stage (2.5 (2.0, 3.0) vs 2.0 (1.5, 2.5), P<0.01).TCS revealed that patients with RLS symptoms were more likely to have abnormality in the raphe nucleus (21.50% vs 7.78%, χ²=15.9, P<0.001) and increased third ventricle width ((6.22±1.97) mm vs (5.16±1.90) mm, P<0.001). No significant differences were found regarding parameters of substantia nigra. Conclusions: Concurrent RLS symptoms are common in PD patients. Abnormal echogenicity of raphe nucleus and increased third ventricle width could be characteristics of TCS in PD patients with RLS symptoms.

LINC00675 suppresses proliferative, migration and invasion of clear cell renal cell carcinoma via the Wnt/β-catenin pathway

OBJECTIVE

To clarify the role of LINC00675 in affecting the progression of clear cell renal cell carcinoma (ccRCC) and its potential mechanism, thus providing effective hallmarks and therapeutic targets for the clinical treatment of ccRCC.

MATERIALS AND METHODS

Differentially expressed long non-coding RNAs (lncRNAs) in renal epithelial tissues and ccRCC tissues were searched by analyzing the dataset downloaded from The Cancer Genome Atlas (TCGA) and LINC00675 was selected. LINC00675 level in ccRCC cell lines was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Overexpression model of LINC00675 model in 786-O and 769-P cells was constructed by the transfection of pcDNA3.1(+)-LINC00675 (LV-LINC00675). Changes in proliferative, migratory, and invasive capacities of 786-O and 769-P cells overexpressing LINC00675 were assessed. At last, relative levels of β-catenin, Vimentin, and N-cadherin in ccRCC cells overexpressing LINC00675 were detected by qRT-PCR and Western blot.

RESULTS

LINC00675 was downregulated in ccRCC tissues and cell lines. Overexpression of LINC00675 attenuated proliferative, migratory, and invasive capacities of 786-O and 769-P cells. Downregulation in β-catenin after overexpression of LINC00675, while Vimentin and N-cadherin levels did not change.

CONCLUSIONS

LINC00675 is downregulated in ccRCC. Overexpression of LINC00675 attenuates ccRCC to proliferate, migrate, and invade by activating the Wnt/β-catenin pathway.

Inactivation of TMEM106A promotes lipopolysaccharide-induced inflammation via the MAPK and NF-κB signaling pathways in macrophages

Pattern recognition receptors, such as Toll-like receptors (TLRs), play an important role in the host defense against invading microbial pathogens. Their activation must be precisely regulated, as inappropriate activation or overactivation of TLR signaling pathways may result in inflammatory disorders, such as septic shock or autoimmune diseases. TMEM106A is a type II transmembrane protein constitutively expressed in macrophages. Our current study demonstrated that TMEM106A levels were increased in macrophages upon lipopolysaccharide (LPS) stimulation, as well as in the peripheral monocytes of patients with sepsis. Tmem106a knockout mice were more sensitive to lipopolysaccharide (LPS)-induced septic shock than wild-type mice. Further experiments indicated that Tmem106a ablation enhanced the expression of CD80, CD86 and major histocompatibility complex (MHC)-II in mouse macrophages upon LPS stimulation, accompanied with up-regulation of tumor necrosis factor (TNF)-α, interleukin (IL)-6, interferon (IFN)-β and inducible nitric oxide synthase (iNOS), indicating the activation of macrophages and polarization towards the M1 inflammatory phenotype. Moreover, elevated mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling were found to be involved in the LPS-induced inflammatory response in Tmem106a^-/- macrophages. However, this effect was largely abrogated by macrophage deletion in Tmem106a^-/- mice. Therefore, deficiency of Tmem106a in macrophages may enhance the M1 polarization in mice, resulting in inflammation. This suggests that TMEM106A plays an important regulatory role in maintaining macrophage homeostasis.

Effects of N-carbamylglutamate and L-arginine on gonadotrophin-releasing hormone (GnRH) gene expression and secretion in GT1-7 cells

Recent studies have shown that N-carbamylglutamate (NCG) and arginine (ARG) supplementation improves reproductive performance in livestock. The objectives of the present study were to evaluate the effects of NCG and ARG on GT1-7 cell gonadotrophin-releasing hormone (GnRH) secretion, gene expression and cell proliferation. GT1-7 cells were treated in vitro with different concentrations of NCG (0-1.0mM) or ARG (0-4.0mM) in serum-free medium for 12 or 24h. For GnRH secretion and cell proliferation, GT1-7 cells were more sensitive to NCG than ARG. NCG treatment after 12h increased cell numbers and inhibited GnRH secretion in a dose-dependent manner (P<0.05), although there was no significant effect of NCG on these parameters after 24h culture. ARG treatment decreased GnRH secretion after 24h (P<0.05), whereas it had no effect after 12h. GT1-7 cells express GnRH, Kiss-1 metastasis-suppressor (Kiss1), G-protein coupled receptor 54 (GPR54), neuronal nitric oxide synthase (nNOS) and estrogen receptor α (ERα) genes. High concentrations of NCG (1.0mM) and ARG (4.0mM) inhibited (P<0.05) GnRH and nNOS mRNA abundance in GT1-7 cells. ARG treatment decreased Kiss1 and increased ERα mRNA abundance. Thus, high concentrations of NCG (1.0mM) and ARG (4.0mM) may act both directly and indirectly to regulate GnRH neuron function by downregulating genes related to GnRH synthesis and secretion to slow GnRH production while stimulating GT1-7 cell proliferation.

Effects of N-carbamylglutamate and arginine on steroidogenesis and proliferation of pig granulosa cells in vitro

Results of in vivo studies indicate dietary N-carbamylglutamate (NCG) and arginine (ARG) can enhance reproductive performance in gilts. It was hypothesized that both NCG and ARG will alter hormone-induced estradiol (E2) production by granulosa cells (GC), explaining why these compounds could improve reproductive performance in pigs. The objective of these studies, therefore, was to evaluate the direct effects of NCG and ARG on porcine GC proliferation and steroidogenesis, using an in vitro cell culture system. The GC from small (SM; 1-5 mm) and large (LG; >5 mm) pig follicles were cultured for 2 days in 5% fetal bovine serum and 5% porcine serum-containing medium followed by 2 days in serum-free medium containing 500 ng/mL of testosterone (as an E2 precursor), and NCG or ARG at various doses in the presence of either follicle-stimulating hormone (FSH; 30 ng/mL), insulin-like growth factor-1 (IGF1; 30 ng/mL), or both. Numbers of GC were determined at the end of the experiment and concentrations of progesterone (P4) and E2 in culture medium were determined. Results indicated that LG-follicle GC were more responsive to NCG and ARG than SM-follicle GC. Specifically, in LG-follicle GC, NCG inhibited (P <  0.05) basal and FSH-induced P4 and E2 production but stimulated cell numbers; whereas ARG inhibited FSH-induced E2 production and cell numbers. In SM-follicle GC, treatment with NCG and ARG decreased IGF1 plus FSH induced P4 production, but E2 production and cell proliferation were not affected. These studies indicate that NCG and ARG may directly affect follicular function in pigs.

Development and validation of a primate model for liver fibrosis

INTRODUCTION

Many liver diseases involve liver fibrosis. Most preclinical studies of liver fibrosis are carried out in small animals such as rodents, and thus lack direct potential for extrapolation to human diseases. The aim of the current study was to develop a primate model for liver fibrosis with greater relevance to translational research.

METHODS

Liver fibrosis was induced in adult male healthy rhesus monkeys using repeated CCl₄ treatment (40% in olive oil, 1.5 ml/kg once every 3 days via peritoneal injection, subcutaneous injection or gastric gavage). Liver biopsy was conducted at various time points for histologic examination. Blood samples were taken for standard liver function test.

RESULTS

Gastric gavage was the optimal approach for establishing stably liver fibrosis without animal loss due to toxicity. The progression of fibrosis appeared to involve epithelial to mesenchymal transition and hepatic ductular reaction.

CONCLUSION

Repeated CCl₄ gavage in rhesus monkeys results in stable liver fibrosis. Such a model may be an effective platform for future studies of human liver fibrosis.

[Genetic variation in DNA polymerase kappa gene is associated with the prognosis after platinum-based chemotherapy in small cell lung cancer patients]

Objective: To investigate the associations between genetic variations of DNA polymerase kappa (POLK) and treatment response to platinum-based chemotherapy of small cell lung cancer (SCLC), and to analyze the influencing factors on survival. Methods: Five haplotype-tagging single nucleotide polymorphisms (htSNPs) of POLK were genotyped by Sequenom MassARRAY methods in 1 030 SCLC patients who received platinum-based chemotherapy, and had different response and survival time. The associations between SNPs and treatment response were analyzed by computing the odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression model. Cox regression was used for survival analysis between SNPs and overall survival by computing the hazard ratios (HRs) and 95% CIs. Results: Among 1 030 cases, 558 (54.2%) cases received cis-platinum and etoposide treatment while others treated with carboplatin and etoposide. Seven hundred and eighty eight patients were chemotherapy responders in the study with a response rate of 76.5%. The median follow-up time of these patients was 22.0 months. Patients were followed up to get their survival information. The median survival time of these patients was 22.5 months. Six hundred and seventy three patients (65.3%) had died by the last date of follow-up to get their survival information (Dec 21, 2017). Five htSNPs of POLK were not associated with the chemotherapy response of SCLC patients who received platinum-based chemotherapy (all P>0.05). Multivariate Cox proportional hazards regression model analysis showed that, rs73120833 of POLK was significantly associated with the overall survival (OS) of SCLC patients, compared with POLK rs73120833 T allele, C allele can prolong OS (adjusted HR=0.87, 95% CI=0.77-0.97, P=0.021). The remaining 4 SNPS, including rs10077427, rs3756558, rs4549504 and rs5744545, were not significantly associated with overall survival. Age≤56, KPS> 80, limited-stage, chemotherapy response and radiation therapy can remarkably prolong OS (all P<0.05). Conclusion: These results suggest that POLK genetic polymorphism rs73120833 plays an important role on the prognosis of SCLC patients, which can be potential genetic biomarker for SCLC personalized treatment.

Modifying the transition temperature, 120 K ≤ Tc ≤ 1150 K, of amorphous Fe90-xCoxSc10 with simultaneous alteration of fluctuation of exchange integral up to zero

Amorphous (a-) Fe_90−xCo_xSc₁₀ alloys have been produced by rapid quenching from the melt. The Curie temperature, T_C, was determined using both mean field theory and Landau’s theory of second-order phase transitions in zero and non-zero external fields. The dependence of T_C on the atomic spacing can be explained by the empirical Bethe-Slater curve. The value of T_C of a- Fe₅Co₈₅Sc₁₀, determined by the above theoretical approaches is 1150 K, which is the highest T_C ever measured for amorphous alloys. The flattening of the measured normalized magnetization, M(T)/M(0), as a function of the reduced temperature, T/T_C, is explained within the framework of the Handrich- Kobe model. According to this model the fluctuation of the exchange integral is the main reason for the flattening of M(T)/M(0). In the case of a-Fe₉₀Sc₁₀ without Co, however, the fluctuation of the exchange integral is dominant only at zero external field, B_ex = 0. At B_ex = 9 T, however, the fluctuation of the exchange integral has no conspicuous effect on the reduction of the magnetization. It is shown that at B_ex = 9 T the frozen magnetic clusters control the behaviour of the reduced magnetization as function of T/T_C. In contrast to other ferromagnetic alloys, where the flattening of M(T)/M(0) is characteristic for an amorphous structure, the a- Fe₅Co₈₅Sc₁₀ does not exhibit any trace of the fluctuation of the exchange integral.

Wave nature of conduction electrons in amorphous Co90Sc10 and Fe90Sc10 alloys

The resistivity of amorphous Fe₉₀Sc₁₀ and Co₉₀Sc₁₀ alloys can be described well in terms of a simple model based on the wave character of electrons and their associated tunnelling over the temperature ranges ~1.9 K to 135 K and ~1.9 K to 12 K respectively. The extended range of agreement between experiment and theory for amorphous Fe₉₀Sc₁₀ is linked with its relatively small mean free path of [Formula: see text]  =  0.32 nm, thus allowing electron waves to tunnel between clusters. On the other hand the restricted region of tunnelling of electron waves for amorphous Co₉₀Sc₁₀ alloys is linked with its relatively large mean free path of [Formula: see text]  =  0.48 nm which restricts the ability for tunnelling between clusters while enabling electron waves to tunnel between different regions with a cluster.

Diabetes mellitus, blood glucose and the risk of heart failure: A systematic review and meta-analysis of prospective studies

BACKGROUND AND AIM

The strength of the association between diabetes and risk of heart failure has differed between previous studies and the available studies have not been summarized in a meta-analysis. We therefore quantified the association between diabetes and blood glucose and heart failure in a systematic review and meta-analysis.

METHODS AND RESULTS

PubMed and Embase databases were searched up to May 3rd 2018. Prospective studies on diabetes mellitus or blood glucose and heart failure risk were included. A random effects model was used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs). Seventy seven studies were included. Among the population-based prospective studies, the summary RR for individuals with diabetes vs. no diabetes was 2.06 (95% CIs: 1.73-2.46, I² = 99.8%, n = 30 studies, 401495 cases, 21416780 participants). The summary RR was 1.23 (95% CI: 1.15-1.32, I² = 78.2%, n = 10, 5344 cases, 91758 participants) per 20 mg/dl increase in blood glucose and there was evidence of a J-shaped association with nadir around 90 mg/dl and increased risk even within the pre-diabetic blood glucose range. Among the patient-based studies the summary RR was 1.69 (95% CI: 1.57-1.81, I² = 85.5%, p_{heterogeneity}<0.0001) for diabetes vs. no diabetes (n = 41, 100284 cases and >613925 participants) and 1.25 (95% CI: 0.89-1.75, I² = 95.6%, p_{heterogeneity}<0.0001) per 20 mg/dl increase in blood glucose (1016 cases, 34309 participants, n = 2). In the analyses of diabetes and heart failure there was low or no heterogeneity among the population-based studies that adjusted for alcohol intake and physical activity and among the patient-based studies there was no heterogeneity among studies with ≥10 years follow-up.

CONCLUSIONS

These results suggest that individuals with diabetes are at an increased risk of developing heart failure and there is evidence of increased risk even within the pre-diabetic range of blood glucose.

Comparison of Single Piece of Dandruff DNA Extraction under Microscope and EZ-tape Method

OBJECTIVES

To collect single piece of dandruff with microscopes to improve the regular EZ-tape method for DNA extraction and genotyping, increase the utilization of samples, reduce the miss rate as well as the proportion of genotyping results of mixed stains.

METHODS

The insides of the hats worn by two volunteers were stuck by EZ-tape and scotch tape respectively. DNA on EZ-tape was directly extracted using traditional method. Single piece of dandruff was collected from the scotch tapes under microscope. The two kinds of methods were both performed under continuous oscillation and standing digestion, respectively. DNA was extracted through Chelex-100 method, and STR genotypes were obtained after amplification and electrophoresis. The results of STR genotypes obtained by EZ-tape method and single piece of dandruff analytical method were compared.

RESULTS

Miss detections happened in 11 samples （45.8%） by EZ-tape method and only single-source typing results were obtained. Ten samples （41.7%） showed the genotype results of mixed stain and six of which showed allele insertions and deletions. The genotype results were obtained successfully using the single piece of dandruff analytical method, and two samples showed mixed stain genotype. The number of exact typing processed by oscillation was higher than that by standing digestion （ P<0.05）.

CONCLUSIONS

The oscillation during the DNA extraction process is in favour of the DNA releasing. Single piece of dandruff analytical method can be used to obtain single-source STR genotype with high successful ratio and low miss rate. This method can be a collection method of special samples such as dandruff in forensic practice.

[Genetic variations in MLH3 and MSH2 genes are associated with the sensitivity and prognosis in locally advanced rectal cancer patients receiving preoperative chemoradiotherapy]

Objective: To investigate the associations between genetic variations in DNA mismatch repair genes and sensitivity as well as prognosis to preoperative chemoradiotherapy in patients with locally advanced rectal cancer. Methods: Fourteen haplotype-tagging single nucleotide polymorphisms (htSNPs) of MLH1, MLH3 and MSH2 genes were genotyped by Sequenom MassARRAY method in 146 patients with locally advanced rectal cancer who received preoperative chemoradiotherapy. The associations between genotypes and response to capecitabine-based neoadjuvant chemoradiotherapy (nCRT) were measured by odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for sex, age, clinical stages and karnofsky performance score (KPS) by unconditional logistic regression model. The survival analyses were performed by the hazard ratios (HRs) and 95% CIs by Cox proportional regression model. Results: Among 146 cases, 64 patients were nCRT responders with a response rate of 43.8%. MLH3 rs175057 C>T and MSH2 rs13019654 G>T loci were associated with the sensitivity to preoperative chemoradiotherapy. Compared with the rs175057 CC genotype, the adjusted OR for patients with CT and TT genotypes was 0.42 (95% CI: 0.19-0.91; P=0.029). Moreover, for rs13019654, the adjusted OR for patients with the GT or TT genotypes was 0.49 (95% CI: 0.24-0.98; P=0.047) than those with GG genotype. The remaining 12 SNPs, including rs1540354, rs4026175, rs1981929, rs2042649, rs2303428, rs3771273, rs4608577, rs4952887, rs6544991, rs6544997, rs10188090 and rs10191478, were not significantly associated with therapeutic response to preoperative chemoradiotherapy. Meanwhile, MLH3 rs175057 C>T locus was also associated with longer overall survival time in locally advanced rectal cancer (HR=0.44, 95% CI: 0.20-0.96, P=0.038), whereas MSH2 rs3771273 T>A, rs10188090 A>G and rs10191478 T>G loci were associated with shorter overall survival time (HR=1.74, 95% CI: 1.06-2.84, P=0.028; HR=1.64, 95% CI: 1.01-2.66, P=0.046; HR=1.71, 95% CI: 1.01-2.91, P=0.047, respectively). The remaining 10 SNPs, including rs1540354, rs4026175, rs1981929, rs2042649, rs2303428, rs4608577, rs4952887, rs6544991, rs6544997 and rs13019654, were not significantly associated with prognosis. Conclusions: Genetic polymorphisms of MLH3 rs175057 and MSH2 rs13019654 loci can predict the nCRT response, while MLH3 rs175057 as well as MSH2 rs3771273, rs10188090 and rs10191478 may predict prognosis in patients with locally advanced rectal cancer who received preoperative chemoradiotherapy. Therefore, these SNPs could be used as potential genetic markers in the personalized therapy of rectal cancer.

N-octanoylated ghrelin peptide inhibits bovine oocyte meiotic resumption

BACKGROUND

Studies have shown that ghrelin plays an important role in the mammalian reproductive system, including the central, gonadal levels, and also during in vitro maturation of oocytes; however, the functions of ghrelin in bovine oocyte meiosis require further investigation.

OBJECTIVE

We aimed to evaluate the effects of an n-octanoylated ghrelin peptide on oocyte meiotic resumption and the developmental competence of mature oocytes in vitro.

EXPERIMENTAL

design: The expression of GHRL (encoding ghrelin) mRNA and its receptor (the growth hormone secretagogue receptor, GHSR) in the cumulus-oocyte complex (COCs), denuded oocytes (DOs), and cumulus cells (CCs) was assessed using quantitative real-time reverse transcription PCR (qRT-PCR), and the effects of the n-octanoylated ghrelin peptide on meiotic resumption were studied at four different doses (0, 10, 50, and 100 ng/mL) in a 6 h culture system.

RESULTS

qRT-PCR analysis showed that GHRL and GHSR mRNAs were expressed in all tested samples; however, GHRL was predominantly expressed in DOs, and GHSR was predominantly expressed in CCs. Germinal vesicle breakdown was inhibited significantly by 50 ng/mL ghrelin compared with that in the negative control (P < 0.05). Further studies showed that n-octanoylated ghrelin increased the levels of cAMP and cGMP in the CCs and DOs, which inhibited the meiotic resumption of bovine oocytes. And the inhibitory role in the developmental competence of mature oocytes were also included, ghrelin could significantly improve the cleavage rate (P < 0.05) and blastocyst rate (P < 0.05).

CONCLUSION

N-octanoylated ghrelin maintained bovine oocytes meiotic arrest and further improved their developmental competence; therefore, n-octanoylated ghrelin could be considered as a potential pharmaceutical inhibitor of meiosis for the in vitro maturation of bovine oocytes.

Electrical resistivity and wave character of free electrons in amorphous and nanoglass Sc75Fe25

The residual electrical resistivity of metallic amorphous alloys, ρ ₀, is typically in the range 50 µΩ cm  <  ρ ₀  <  310 µΩ cm corresponding to a mean free path of conduction electrons of order a few interatomic distances. In crystalline metals with low defect levels such as Cu however, the residual electrical resistivity is about ρ ₀  ≈  1.54  ×  10^-2 µΩ cm, leading to extensive progression of free electrons through the crystalline material, of typically up to 4  ×  10⁶ nm. The relatively 'high' values for the electrical resistivity of distorted Sc₇₅Fe₂₅ alloys are discussed here within the framework of the wave character of electrons. The present investigation of amorphous and nanoglass Sc₇₅Fe₂₅ over the temperature range 1.9-320 K, focuses on clarification of the temperature dependence of the resistivity, ρ(T). These alloys systems, which show a range of behaviours for temperature dependent resistivity-including temperature independent residual resistivity, as well as positive and negative polarities for the slope dρ(T)/dT-are examined in detail.

Effect of melatonin on bovine theca cells in vitro

Melatonin affects granulosa cell function in several species but its function in theca cells is less clear, particularly in monotocous animals. Thus, the objectives of this study were to determine the effects of melatonin on theca cell steroidogenesis, gene expression and cell proliferation in a monotocous species, namely cattle. Ovaries were collected from a local bovine abattoir, from which theca cells were isolated from large (8–22 mm) follicles and treated with various hormones in serum-free medium for 24 h or 48 h. Melatonin caused a dose-dependent inhibition (P < 0.05) of LH+insulin-like growth factor 1 (IGF1)-induced androstenedione and progesterone production. Also, melatonin inhibited (P < 0.05) LH+IGF1-induced expression of steroidogenic acute regulatory protein (StAR) mRNA (via real-time polymerase chain reaction) in theca cells, but it had no effect (P > 0.10) on cytochrome P450 11A1 (CYP11A1) and cytochrome P450 17A1 (CYP17A1) mRNA abundance. In LH+IGF1-treated theca cells, melatonin decreased caspase 3 (CASP3) mRNA to levels similar to those observed in LH-treated theca cells. In contrast, melatonin increased (P < 0.05) the number of bovine theca cells in both LH- and LH+IGF1-treated cultures. In conclusion, melatonin may act as an endocrine regulator of ovarian function in cattle by stimulating theca cell proliferation and inhibiting differentiation via inhibition of hormone-induced steroidogenesis.