
- Login
- Register
- Home/Current Issue
- About the journal
- Editorial board
- Online submission
- Instructions for authors
- Subscriptions
- Foundation Acta Endocrinologica
- Archive
- Contact



ACTA ENDOCRINOLOGICA (BUC)
The International Journal of Romanian Society of Endocrinology / Registered in 1938in Web of Science Master Journal List
Acta Endocrinologica(Bucharest) is live in PubMed Central
Journal Impact Factor - click here.

-
General Endocrinology
Radian S, Bensaada M, Lautier C, Moles JP, Grigorescu F, Gussi I, Badiu C, Nastasia S, Hudita D, Leonte L, Marinescu B, Coculescu M
Molecular genetics strategies to identify vasotocin coding sequences in humans: family-specific approach using genomic DNA and fetal tissues mRNAsActa Endo (Buc) 2005 1(2): 131-144 doi: 10.4183/aeb.2005.131
Abstract ReferencesVertebrate nonapeptide neurohormones constitute an evolutionarily conserved family, involved in vital functions, such as hydro-osmotic balance regulation, reproduction and social behaviour. Two human members of this family are known, vasopressin (AVP) and oxytocin (OXT), with their highly homologous genes closely located on Chr 20p13. Presence of vasotocin (AVT) in man has been suggested, but remains controversial, and genetic evidence is lacking. AVT activity could be explained by the presence of a third distinct gene for AVT or an RNA-processing mechanism involving products of AVP and/or OXT genes. To test the first hypothesis, we developed bioinformatics and experimental approaches using genomic DNA and fetal tissues mRNAs. Family-specific primers for AVT and neurophysin were designed based on CODEHOP strategy and used in our experiments. Results of bioinformatics and genomic DNA experiments (family-specific and Alu step-out PCR) suggest there is no evidence for an AVT gene in the genome. RNA-based techniques 3?-RACE and Family-Specific Domain Restriction Fragment RTPCR provided evidence for new transcript species that could code for AVT. Further experiments will be needed to characterize them. We discuss potential mechanisms of AVT mRNA generation based on AVP and OXT mRNAs, by alternative splicing, heterologous transsplicing or RNA-editing. While all methods we developed proved feasible, current results suggest there is no AVT gene in the genome, but specific mRNAs could be present in fetal tissues. Their full characterization may potentially allow identification of vasotocin mRNA and shed light on a subject of fundamental scientific interest.1. Dale HH. Evidence concerning the endocrine function of the neurohypophysis and its nervous control. In: The Neurohypophysis, editor Heller HH. London: Butterworth?s, 1957, 1-9.2. Dantzer R. Vasopressin, gonadal steroids and social recognition. Prog Brain Res. 1998;119:409-14.3. Bielsky IF, Young LJ. Oxytocin, vasopressin, and social recognition in mammals. Peptides. 2004;25(9):1565-74. [CrossRef]4. Kosfeld M, Heinrichs M, Zak PJ, Fischbacher U, Fehr E. Oxytocin increases trust in humans. Nature. 2005;435(7042):673-6. [CrossRef]5. Hoyle CH. Neuropeptide families and their receptors: evolutionary perspectives. Brain Res. 1999;848(1-2):1-25. [CrossRef]6. Sausville E, Carney D, Battey J.The human vasopressin gene is linked to the oxytocin gene and is selectively expressed in a cultured lung cancer cell line. J Biol Chem. 1985;260(18):10236-41.7. Pavel, S. Arginine vasotocin as a pineal hormone. J. Neural. Transmission 1978; 13:135-155.8. Coculescu M, Pavel S. Arginine vasotocin-like activity of cerebrospinal fluid in diabetes insipidus. J Clin Endocrinol Metab. 1973;36(5):1031-2. [CrossRef]9. Catrina SB, Coculescu M, Andersson M. A chemical method to isolate hypothalamic nonapeptides by coupling cyst(e)in with bimane. J Cell Mol Med. 2001;5(2):195-7. [CrossRef]10. Badiu C, Coculescu M, Moller M. Arginine vasotocin mRNA revealed by in situ hybridization in bovine pineal gland cells. Cell Tissue Res. 1999;295(2):225-9. [CrossRef]11. Ervin MG, Amico JA, Leake RD, Ross MG, Robinson AG, Fisher DA. Arginine vasotocin and a novel oxytocin-vasotocin-like material in plasma of human newborns. Biol Neonate. 1988;53(1):17-22. [CrossRef]12. Pavel S. Evidence for the ependymal origin of arginine vasotocin in the bovine pineal gland. Endocrinology. 1971;89(2):613-4. [CrossRef]13. Pavel S, Dorcescu M, Petrescu-Holban R, Ghinea E. Biosynthesis of a vasotocin-like peptide in cell cultures from pineal glands of human fetuses. Science. 1973;181(106):1252-3. [CrossRef]14. Rose TM, Schultz ER, Henikoff JG, Pietrokovski S, McCallum CM, Henikoff S. Consensusdegenerate hybrid oligonucleotide primers for amplification of distantly related sequences. Nucleic Acids Res. 1998;26(7):1628-35. [CrossRef]15. <http://blocks.fhcrc.org/blocks/codehop.html>16. Fuentes JJ, Pucharcos C, Pritchard M, Estivill X. Alu-splice PCR: a simple method to isolate exoncontaining fragments from cloned human genomic DNA. Hum Genet. 1997;101(3):346-50. [CrossRef]17. Siebert PD, Chenchik A, Kellogg DE, Lukyanov KA, Lukyanov SA. An improved PCR method for walking in uncloned genomic DNA. Nucleic Acids Res. 1995;23(6):1087 [CrossRef]18. Matz M, Shagin D, Bogdanova E, Britanova O, Lukyanov S, Diatchenko L, Chenchik A. Amplification of cDNA ends based on template-switching effect and step-out PCR. Nucleic Acids Res. 1999;27(6):1558-60. [CrossRef]19. Michel G, Levy B, Chauvet MT, Chauvet J, Acher R. Complete amino acid sequence of goose VLDVneurophysin. Traces of a putative gene conversion between promesotocin and provasotocin genes. Int J Pept Protein Res. 1990;36(5):457-64. [CrossRef]20. Ruppert S, Scherer G, Schutz G. Recent gene conversion involving bovine vasopressin and oxytocin precursor genes suggested by nucleotide sequence. Nature. 1984 Apr 5-11;308(5959):554-7. [CrossRef]21. Pavel S. Evidence for the presence of lysine vasotocin in the pig pineal gland. Endocrinology. 1965 ;77(5):812-7. [CrossRef]22. Pavel S. Pineal vasotocin and sleep. Environmental Physiology. Vol. 18 in Advances in Physiological Sciences. Proceedings of the 28th International Congress of Physiological Sciences, Budapest, 1980. Obal, F., and G. Benedek, Eds. Budapest: Akademiai Ki23. Coculescu M, Serbanescu A, Temeli E. Influence of arginine vasotocin administration on nocturnal sleep of human subjects. Waking Sleeping. 1979;3(3):273-7.24. Mihai R, Coculescu M, Wakerley JB, Ingram CD. The effects of [Arg8]vasopressin and [Arg8]vasotocin on the firing rate of suprachiasmatic neurons in vitro. Neuroscience. 1994 ;62(3):783-92. [CrossRef]25. Lefebvre DL, Zingg HH. Novel vasopressin gene-related transcripts in rat testis. Mol Endocrinol. 1991;5(5):645. [CrossRef]26. Foo NC, Funkhouser JM, Carter DA, Murphy D. A testis-specific promoter in the rat vasopressin gene. J Biol Chem. 1994;269(1):65.27. Caudevilla C, Serra D, Miliar A, Codony C, Asins G, Bach M, Hegardt FG. Natural trans-splicing in carnitine octanoyltransferase pre-mRNAs in rat liver. Proc Natl Acad Sci U S A. 1998;95(21):12185-90. [CrossRef]28. Finta C, Zaphiropoulos PG. Intergenic mRNA molecules resulting from trans-splicing. J Biol Chem. 2002;277(8):5882-90. Epub 2001 Nov 28. [CrossRef]29. Mohr E, Peters A, Morris JF, Richter D. Somatic nonhomologous crossing-over between neuropeptide genes in rat hypothalamic neurons. Proc Natl Acad Sci U S A. 1994;91(24):11403-7. [CrossRef]30. Eisenberg E, Nemzer S, Kinar Y, Sorek R, Rechavi G, Levanon EY. Is abundant A-to-I RNA editing primate-specific? Trends Genet. 2005;21(2):77-81. [CrossRef]31. Levanon EY, Eisenberg E, Yelin R, Nemzer S, Hallegger M, Shemesh R, Fligelman ZY, Shoshan A, Pollock SR, Sztybel D, Olshansky M, Rechavi G, Jantsch MF. Systematic identification of abundant Ato- I editing sites in the human transcriptome. Nat Biotechnol [CrossRef] -
Perspectives
Mori K, Emoto M, Numaguchi R, Numaguchi R, Yamazaki Y, Urata H, Motoyama K, Morioka T, Shoji T, Inaba M
Potential Advantage of Repaglinide Monotherapy in Glycemic Control in Patients with Type 2 Diabetes and Severe Renal ImpairmentActa Endo (Buc) 2017 13(2): 133-137 doi: 10.4183/aeb.2017.133
AbstractContext. Oral anti-diabetic drugs (OADs) are leading option for treatment of type 2 diabetes (T2D). However, availability of OADs are limited in the presence of renal impairment (RI). Objective. In this study, we examined the efficacy of repaglinide, which is mainly metabolized and excreted via non-renal route, in patients with T2D and severe RI that consists mainly of chronic kidney disease (CKD) stage 4. Design, Subjects and Methods. This was an open label, single arm, interventional study by repaglinide monotherapy. The primary efficacy end point was HbA1c change from baseline to week 12. Results. Repaglinide treatment significantly reduced HbA1c levels from 7.7 ± 0.7% to 6.1 ± 0.3% (p<0.001) in 9 patients with severe RI (mean estimated glomerular filtration rate was 26.4 ± 7.5 mL/min/1.73m2). Focusing on 4 patients who received DPP-4 inhibitor monotherapy at enrolment, switching to repaglinide also significantly improved HbA1c levels. No hypoglycemic symptoms or severe hypoglycemia was reported in patients who completed the period of 12 weeks. Conclusions. We demonstrated the efficacy of repaglinide in patients with T2D and severe RI. In case that DPP-4 inhibitors are not enough to achieve targeted range of glycemic control, repaglinide is another good candidate. -
Notes & Comments
Topaloglu O, Evren B, Uzun M, Yologlu S, Guldogan E, Sahin I
Is There a Relationship between Serum IGF-1 and Thyroid Nodule, Thyroid or Ovarian Volume in Polycystic Ovarian Syndrome?Acta Endo (Buc) 2021 17(1): 138-146 doi: 10.4183/aeb.2021.138
AbstractContext. Studies investigating the association between serum IGF-1, and thyroid nodule, ovarian or thyroid volume in polycystic ovarian syndrome (PCOS) are limited. Objective. We aimed to analyze the association between serum IGF-1 level, and ovarian or thyroid volume, or thyroid nodule in PCOS. Design. The study was performed between June 2017 and August 2019 as prospective design. Subjects and Methods. Adult females with newonset PCOS were included. The patients having comorbid illness, or using medication were excluded. Basic tests, thyroid and ovarian sonography were performed. The patients were grouped according to thyroid nodule(absent/ present) and ovarian volume (<10mL/≥10mL). We planned to find a positive association between IGF-1, and thyroid nodule, thyroid or ovarian volume in PCOS. Results. Of total 118 patients, 11(9%) had thyroid nodule. The patients with thyroid nodule had a higher ovarian volume (p=0.006). No correlation was found between GH or IGF-1, and thyroid or ovarian volume. IGF-1 was not a predictor for thyroid nodule or higher ovarian volume. Thyroid nodule was a significant predictor for higher ovarian volume. Conclusion. Our study is the first to analyze the association between IGF-1 and thyroid nodule in PCOS. We found that thyroid nodule was associated with thyroid and ovarian volume, but IGF-1 was not associated with thyroid nodule, thyroid or ovarian volume. -
General Endocrinology
Lutescu I, Gussi I, Banceanu G, Coculescu M
Specific changes of blood-brain-barrier permeability for estrogens and gonadotrophins at menopauseActa Endo (Buc) 2007 3(2): 141-148 doi: 10.4183/aeb.2007.141
AbstractIntroduction. Estrogens are known to have a neuroprotective role and to influence the permeability of the blood brain barrier (BBB). An ongoing debate exists on the changing effects of estrogens on target tissues with advancing age and at menopause and on the potential disruptive role of increasing gonadotropin levels.\r\nThe aim of the present study was to assess the permeability of the BBB for estradiol, FSH and LH in three physiological states: early follicular phase, preovulatory phase and at menopause.\r\nMethod. Hormonal levels were assessed simultaneously in the serum and cerebrospinal fluid (CSF) of 15 women at menopause (mean age 60?8 years), 16 of reproductive age in early follicular phase and 11 in preovulatory phase (mean age 31?7 years), all undergoing surgery for benign gynecologic disorders. FSH, LH and estradiol levels were assessed using chemo luminescence and are expressed as median and 10-90 percentile interval. Statistical analysis assessed the serum-CSF correlation and the CSF/serum ratio for each hormone between groups.\r\nResults. Estradiol serum levels were 26.2 pg/ml (6.4-43.5) at menopause (n=15), 58.5 pg/ml (25.7-75.9) in early follicular phase (EFP, n=16) and 221.2 pg/ml (113.7-405.5) in preovulatory phase (PREOV, n=11). CSF estradiol is 18.5 pg/ml (0.4-30.5) at menopause, 5.4 pg/ml (2.2-10.2) in EFP (p<0.001) and 17.3 pg/ml (10.3-34.6) in PREOV patients. Estradiol serum and CSF levels correlate positively in the fertile cycle (r=0.72, p<0.0001) and negatively at menopause (r=-0.88, p<0.05). The CSF/serum ratio for estradiol is 0.8 (0.01-4.4) at menopause, 0.1 (0.04-0.13) in EFP and 0.1 (0.03-0.13) in PREOV patients. FSH serum levels were 75.8 mUI/ml (35.9-129.8) at menopause, 7.7 mUI/ml (3.5-11.4) in EFP and 7.3 mUI/ml (3.1-10.7) in PREOV patients. CSF FSH is 2.7 mUI/ml (0.4- 5.9) at menopause, significantly higher than 0.7 mUI/ml (0.3-1) in EFP (p<0.001) and 0.5 mUI/ml (0.2-1) in PREOV patients (p<0.05). FSH serum and CSF levels correlate positively in the fertile cycle (r=0.8, p<0.0001) and do not correlate at menopause (p=NS). The CSF/serum ratio for FSH is 0.03 (0.01-0.1) at menopause, significantly lower than 0.09 (0.06-0.16) in EFP (p<0.001) and is 0.06 (0.03-0.13) in PREOV phase. LH serum levels were 57.4 mUI/ml (27.5-84.8) at menopause, 4.7 mUI/ml (1.7-7.1) in EFP and 5.5 mUI/ml (4.9-8.02) in PREOV phase. CSF LH is 1.6 mUI/ml (0.7-2.6) at menopause, significantly higher than 0.4 mUI/ml (0.1-1) in EFP (p<0.001) and 0.5 mUI/ml (0.2-0.9) in preovulatory phase (p<0.05). The CSF/serum ratio for LH is 0.03 (0.01-0.07) at menopause, it is significantly lower than 0.09 (0.03-0.27) in EFP (p<0.001) and is 0.07 (0.03-0.14) in preovulatory phase.\r\nConclusions. This study shows the negative correlation of serum and CSF estradiol levels at menopause reflecting the need of constant estrogen levels within the CSF despite low chronic serum levels. Simultaneously, the CSF/serum ratio for gonadotrophins is\r\nreduced significantly at menopause and the positive correlation of serum and CSF levels is lost, reflecting a protective mechanism against rising levels of FSH and LH. -
Perspectives
Bozkus Y, Mousa U, Demir CC, Anil C, Kut A, Turhan Iyidir O, Gulsoy Kirnap N, Firat S, Nar A, Tutuncu NB
Abdominal Bioelectric Impedance for Follow-Up of Dieters: a Prospective StudyActa Endo (Buc) 2019 15(2): 145-152 doi: 10.4183/aeb.2019.145
AbstractContext. Visceral adipose tissue (VAT) is a strong predictor of carbohydrate metabolism disorders. Abdominal bioelectrical impedance analysis (A-BIA) is a simple method for the measurement of VAT and is a promising tool in screening and follow-up of abdominal obesity. However the role of A-BIA in dieting individuals has not been evaluated adequately in longitudinal followup studies. Objective. The aim of this study is to determine the role of A-BIA in identifying the changes in metabolic predictors after diet and/or exercise therapy. Design. All patients who sought weight loss treatment underwent baseline assessment and were prescribed a program of diet. After a mean follow-up of 3.2 months, data were analyzed. Subjects and Methods. Ultimately, 103 participants who reported adhering to the diet, enrolled to the study. We tested associations between changes in body composition measures and changes in laboratory measures using correlations and multivariate linear regression analysis. Results. Mean loss of body weight was 3.4±2.8 kg. All but waist-to-hip ratio, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels changed significantly (p<0.001). Decreases in body weight, body mass index (BMI), and VAT level significantly correlated with decreases in fasting blood glucose, fasting insulin level, and HOMA-IR score (r=0.230–0.371). In multiple linear regression analysis changes in BMI and VAT significantly correlated with change in HOMA-IR score (F(7.93)=2.283, p=0.034, R2=0.147). Conclusion. Decreases in BMI and VAT, as determined by A-BIA, were predictors of changes in metabolic laboratory measures. A-BIA is useful for followup of patients receiving diet therapy for weight loss. -
General Endocrinology
Méndez-López LF, Zavala-Pompa A, Fuentes-Vera MA, Pacheco-Calleros J, Escobar-Moreno AC, Cortés-Gutiérrez EI, Dávila-Rodríguez MI
Quantification of Leptin Receptor Expression in Endometrial Tissue Throughout the Human Menstrual CycleActa Endo (Buc) 2015 11(2): 147-154 doi: 10.4183/aeb.2015.147
AbstractLeptin is much more than a simple sensor of body fat levels. Its biological activities, include angiogenesis, osteogenesis and modulation of the immune and reproductive systems. There are no reports on fluctuations of the level in normal human functional glandular epithelium during the menstrual cycle. Objective. We aimed to determine the expression level of the leptin receptor by immunohistochemistry and to correlate this with estrogen and progesterone receptor levels in normal endometrial tissue throughout the menstrual cycle. Study design. Thirty-seven paraffin wax blocks of biopsy specimens of histologically normal endometrium were evaluated and classified according to the stage of the menstrual cycle during the 2004–2006 period. Results. The OB-R level underwent fluctuations during the menstrual cycle in the different tissue compartments; these were most marked in the functional glandular epithelium and during the proliferative stage. OB-R levels were correlated positively with the expression levels of estrogen and negatively with those for progesterone receptors, suggesting that these steroids modulate the expression of OB-R in vivo. Conclusion. This finding underscores the importance of considering the menstrual cycle stage for studies seeking possible impacts of the OB-R on reproductive pathology, because its expression level varies with the hormonal environment. -
General Endocrinology
Can M, Kocabas M, Karakose M, Alsancak Y, Yerlikaya FH, Caliskan Burgucu H, Cordan I, Kadiyoran C, Kulaksizoglu M, Karakurt F
New Biomarkers to Predict Cardiovascular Risk in Patients with Adrenal Incidentaloma; Irisin and Nesfatin-1Acta Endo (Buc) 2022 18(2): 150-155 doi: 10.4183/aeb.2022.150
AbstractObjective. In our study, we aimed to investigate the levels of irisin, nesfatin-1 and the relationship between levels of these relatively new molecules with cardiometabolic risk markers; carotid intima-media thickness (CIMT), epicardial adipose tissue (EAT) thickness in patients with nonfunctional adrenal incidentaloma (NFAI). Materials and Methods. Patients with NFAI (n=59) and age, sex and body mass index-matched healthy control subjects (n=59) were enrolled in this study. Serum glucose, insulin, C-reactive protein (CRP), lipid, irisin and nesfatin-1 levels and echocardiographic CIMT and EAT thickness measurements were performed in patients and controls. Results. The irisin level was 17.58 ± 4.38 pg/mL in the NFAI group, significantly higher (p<0.001) than 14.03 ± 4.03 pg/mL in the control group. Nesfatin-1 level was significantly lower in the NFAI group 194.98 ± 119.15 pg/ mL ((p < 0.001)) versus 303.48 ± 200.78 pg/mL in the control group. A positive correlation was found between irisin and nesfatin-1 levels and CIMT and EAT thickness in the NFAI group. Conclusions. In our study, we found that irisin level was higher and nesfatin-1 level was lower in patients with NFAI, and both irisin and nesfatin-1 levels were associated with CIMT and EAT thickness in NFAI patients. -
Notes & Comments
Ioacara S, Ionescu-Tirgoviste C, Guja C
Life Expectancy in Adult Diabetes Patients Treated with Insulin from DiagnosisActa Endo (Buc) 2012 8(1): 153-162 doi: 10.4183/aeb.2012.153
AbstractAims. To investigate the historical changes in survival with diabetes in patients treated with insulin from diagnosis.\r\nMethods. We analyzed 2811 deaths, 51.5% males, registered at ?I. Pavel? Bucharest Diabetes Centre, aged 40-64 years and deceased between 1943 and 2009. We split the analysis in three time periods according to year of death: 1943-1965,\r\n1966-1988 and 1989-2009.\r\nResults. The mean age at diabetes onset was 51.4?6.8 years, with mean disease duration at death of 17.7?11.6 years\r\nand mean age at death of 69.1?11.2 years. The mean survival after diabetes onset was 13.9?9.8 years in 1943-1965, and rose to 17.3?9.6 years (p<0.001) in 1989-2009. There was a significant increase for coronary heart diseases and cancer and a significant decrease for infections and endstage\r\nrenal disease as causes of death.\r\nConclusions. We found no significant changes in age at onset, which combined with an increase in survival with diabetes lead to a significant increase in age at death.\r\nMajor historical events have a strong impact over survival after the onset of diabetes. -
General Endocrinology
Todorovic J, Dugalic S, Jovandaric M, Stojiljkovic M, Pantic I, Macura M, Perkovic S, Milincic M, Sengul D, Sengul I, Gojnic M
The Importance of Early Detecting of Thyroid Dysfunction During Pregnancy and Association with Gestational Diabetes MellitusActa Endo (Buc) 2024 20(2): 153-161 doi: 10.4183/aeb.2024.153
AbstractObjective. Thyroid dysfunction represents common disorder occurring very frequently among women of reproductive age, including pregnancy. The aim of this literature review was to determine in which way thyroid function during pregnancy is associated with GDM. Design. We conducted review of the literature following the basic principles of literature search. Methods. Two researcher independently searched PubMed in the period of last five years (2018-2023) to identify eligible studies regarding thyroid function and GDM. Results. From 51 papers initially found after the inserting key words in PubMed search field 30 were excluded after the title and abstract review. After reading full text of 21 articles, 15 were included in the review. Conclusions. Our review of literature showed not only that two most common disorders during pregnancy were GDM and thyroid dysfunction, but also indicated that they were in positive correlation. -
General Endocrinology
Guan B, Wang L, Ma L, Liu X, Liu L
Effects of Exendin-4 on Endoplasmic Reticulum Stress-Mediated Insulin Resistance in 3t3-L1 AdipocytesActa Endo (Buc) 2019 15(2): 158-164 doi: 10.4183/aeb.2019.158
AbstractObjective. Endoplasmic reticulum stress (ERS) is suspected as an important factor in the initiation of insulin resistance. Aim. To explore the effects of exendin-4 (Ex- 4) on the endoplasmic reticulum stress (ERS)-mediated insulin resistance in 3T3-L1 adipocytes. In our study, 3T3-L1 adipocytes were pre-treated with ERS inhibitors tauroursodeoxycholic acid (TUDCA), Ex-4 and an ERS inducer tunicamycin (TM) then induced insulin resistance. Glucose consumption of the adipocytes was measured. Western blots determined the protein levels of ERS markers and insulin signaling pathway. Results. TM treatment reduced insulin-stimulated glucose consumption by 19.7% in 3T3-L1 adipocytes. This repression was blunted by 24h pre-treatment with TUDCA or Ex-4. Ex-4 augmented insulin-stimulated glucose consumption in adipocytes by 14.9%. Western blotting showed that TM treatment significantly increased the ER stress markers including p-IRE, p-JNK, p-PERK, p-eIF2a and ATF6 expression, whereas 24h pre-treatment of adipocytes with TUDCA or Ex-4 alleviated the ER stress. Ex-4 alleviates ERS-induced insulin resistance by upregulating the expression of phosphorylated Akt. Conclusion. ERs mediates insulin resistance in 3T3-L1 adipocytes, and exendin-4 significantly improves this insulin resistance.