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1.
Am J Transl Res ; 16(3): 838-854, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586113

RESUMO

OBJECTIVE: To assess how obesity, normal weight (NW) versus overweight/obese (OW/OB), impacts platelet-rich plasma's (PRP) effectiveness during in vitro fertilization and how obesity affects platelets during the menstrual cycle. METHODS: Endometrial mean thickness (EMT), embryo implantation, and clinical pregnancy were assessed using a self-controlled retrospective study that enrolled 59 patients with two failed cycles and treated with autologous PRP (three-dose scheme). The NHANES dataset was used to assess platelet changes during the menstrual cycle, using the mean platelet volume to platelet count ratio (MPR) index. The COSINOR packages for R were used to determine rhythmicity. RESULTS: PRP treatments significantly improved the EMT (2.5 ± 1.4 mm, P<0.001), unaffected by obesity. After the PRP treatment, one patient spontaneously became pregnant; therefore, 58 patients underwent embryo transfer (62 cycles), of which in 39 cycles the embryos implanted (63.9%). This was a significant improvement from their previous cycle (vs. 22.6%, P<0.001). Clinical pregnancy also improved with the PRP treatment over the previous cycle (57.4% vs. 16.1%, P<0.001). When stratified by obesity, there was an appreciable decrease in embryo implantation and clinical pregnancy rates for the OW/OB group; nevertheless, the PRP treatment significantly improved embryo implantation and clinical pregnancy (P<0.05). A rhythm was observed with the MPR index (P<0.05) only for the NW group, suggesting that the platelets normally fluctuate during the menstrual cycle. CONCLUSION: PRP improved embryo implantation and clinical pregnancy rates; however, these beneficial effects were attenuated by obesity. PRP presumptively promoted a change in the uterine environment to mimic the normal findings associated with normal-weight women.

2.
Oxf Med Case Reports ; 2023(4): omad037, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37091684

RESUMO

Limited options are available for infertility associated with damaged or suboptimal tissues, typically the endometrium or ovaries. The goal of regenerative medicine is to restore function to specific tissues. Here, a 35-year-old female patient underwent two interventions of regenerative medicine: (i) autologous mesenchymal stem cells (MSCs) were applied in the myometrium, and (ii) intraovarian infusion of platelet-rich plasma (PRP). After two failed in vitro fertilization cycles (IVF), in which the endometrium was <5 mm, MSCs were applied, achieving a 7 mm trilaminar lining; however, the embryo quality remained poor. Therefore, intraovarian PRP was utilized for the next IVF cycle; the patient's response improved, and a euploid embryo developed. After the embryo transfer and a normal 38 weeks of pregnancy, a baby girl was born. Here, we demonstrate two forms of regenerative medicine that can be utilized to improve IVF.

3.
World J Clin Cases ; 10(33): 12295-12304, 2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36483831

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is an endocrine disease that combines metabolic, reproductive, and psychological dysfunctions. Ovulation disorders and impaired endometrial receptivity in PCOS can cause infertility. Insulin resistance (IR) is a pathological state of inadequate response to insulin that affects reproduction in PCOS, as damage caused by IR at the endometrial level becomes an obstacle for embryo implantation. Reversing IR resulted in spontaneous pregnancies in PCOS patients, indicating that metabolic corrections improve endometrial dysfunctions. Mesenchymal stem-cell treatment has also corrected endometrial quality and lead to pregnancies in patients with Asherman's syndrome. We propose a combination of nutritional intervention with the surgical placement of stem cells to improve endometrial quality to achieve pregnancy in a PCOS patient undergoing in vitro fertilization (IVF) treatment. CASE SUMMARY: After two failed IVF cycles, a metabolic intervention, consisting of a ketogenic diet with daily consumption of 50 g of carbohydrates (CH), was indicated until pregnancy. Metabolic Syndrome was assessed using the Harmonizing Definition (3 of 5 pathologies: Central obesity, hypertension, hyperglycemia, hypertriglyceridemia, and dyslipidemia), and the Homeostatic Model Assessment of IR (HOMA-IR) was used to measure the level of IR. Once IR improved, endometrial quality improved. However, two day 5-thawed embryos (euploid, donated oocyte-partner's sperm) failed to implant, suggesting endometrial quality improvement was insufficient. Therefore, transmyometrial implantation of mesenchymal stem cells from the stromal vascular fraction of adipose tissue was performed to enrich the endometrial stem cell niche. Minimal endometrial mean thickness for embryo transfer (6.9 mm) was achieved three months after stem cell treatment and continuous dietary control of IR. Two euploid-day 5-thawed embryos (donated oocyte-partner's sperm) were transferred, and embryo implantation was confirmed on day 14 by ß-hCG serum levels. Currently, a 37 wk baby girl is born. CONCLUSION: In PCOS, endometrial quality can be improved by combining nutrient-based metabolic correction with endometrial stem cell niche enrichment.

4.
ASN Neuro ; 14: 17590914221116574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903937

RESUMO

SUMMARY STATEMENT: EAAT1/GLAST down-regulates its expression and function at the transcriptional level by activating a signaling pathway that includes PI3K, PKC and NF-κB, favoring the notion of an activity-dependent fine-tuning of glutamate recycling and its synaptic transactions through glial cells.


Assuntos
Transportador 1 de Aminoácido Excitatório , Regulação da Expressão Gênica , Células Cultivadas , Transportador 1 de Aminoácido Excitatório/genética , Transportador 1 de Aminoácido Excitatório/metabolismo , Regulação da Expressão Gênica/genética , Ácido Glutâmico/metabolismo , Neuroglia/metabolismo
5.
Tissue Barriers ; 10(2): 1994351, 2022 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-34689705

RESUMO

ZO-2 is a peripheral tight junction (TJ) protein whose silencing in renal epithelia induces cell hypertrophy. Here, we found that in ZO-2 KD MDCK cells, in compensatory renal hypertrophy triggered in rats by a unilateral nephrectomy and in liver steatosis of obese Zucker (OZ) rats, ZO-2 silencing is accompanied by the diminished activity of LATS, a kinase of the Hippo pathway, and the nuclear concentration of YAP, the final effector of this signaling route. ZO-2 appears to function as a scaffold for the Hippo pathway as it associates to LATS1. ZO-2 silencing in hypertrophic tissue is due to a diminished abundance of ZO-2 mRNA, and the Sp1 transcription factor is critical for ZO-2 transcription in renal cells. Treatment of OZ rats with metformin, an activator of AMPK that blocks JNK activity, augments ZO-2 and claudin-1 expression in the liver, reduces the paracellular permeability of hepatocytes, and serum bile acid content. Our results suggest that ZO-2 silencing is a common feature of hypertrophy, and that ZO-2 is a positive regulator of the Hippo pathway that regulates cell size. Moreover, our observations highlight the importance of AMPK, JNK, and ZO-2 as therapeutic targets for blood-bile barrier dysfunction.


Assuntos
Proteínas Quinases Ativadas por AMP , Fígado Gorduroso , Proteína da Zônula de Oclusão-2/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Via de Sinalização Hippo , Hipertrofia , Ratos , Ratos Zucker , Proteínas de Junções Íntimas
6.
F1000Res ; 11: 997, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38481536

RESUMO

Stem cell technology is a powerful tool ready to respond to the needs of modern medicine that is experiencing rapid technological development. Given its potential in therapeutic applications, intellectual property rights (IPR) as a protection resource of knowledge are a relevant topic. Patent eligibility of stem cells has been controversial as restrictions to access the fundamental technologies open a gap between research and clinic. Therefore, we depicted the current patent landscape in the field to discuss if this approach moves forward in closing this breach by examining patent activity over the last decade from a transdisciplinary perspective. Stem cell therapeutic applications is an area of continuous growth where patent filing through the PCT is the preferred strategy. Patenting activity is concentrated in the USA, European Union, and Australia; this accumulation in a few key players leads to governance, regulation, and inequality concerns. To boost wealthiness and welfare in society - stem cell therapies' ultimate goal - while at post-pandemic recovery, critical elements in the field of IPR rise to overcome current limitations: to promote bridge builders able to connect the research and business worlds, regulatory updates, novel financing models, new vehicles (startups, spinouts, and spin-offs), and alternative figures of intellectual property.


Assuntos
Propriedade Intelectual , Células-Tronco , Comércio , Tecnologia , Terapia Baseada em Transplante de Células e Tecidos
7.
Toxicol Mech Methods ; 30(5): 336-349, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32166990

RESUMO

In cosmetics and food products, parabens are widely used as antimicrobial agents. Reports have suggested that parabens may be linked to infertility, owing to their effects on basal steroidogenesis properties or their capacity to inflict mitochondrial damage. Despite growing concerns about parabens as endocrine disruptors, it is unclear whether they affect any of these actions in humans, particularly at environmentally relevant concentrations. In this work, an in vitro primary culture of human granulosa cells was used to evaluate steroidogenesis, based on the assessment of progesterone production and regulation of critical steroidogenic genes: CYP11A1, HSD3B1, CYP19A1, and HSD17B1. The effects of two commercially relevant parabens, methylparaben (MPB) and butylparaben (BPB), were screened. Cells were exposed to multiple concentrations ranging from relatively low (typical environmental exposure) to relatively high. The effect was assessed by the parabens' ability to modify steroidogenic genes, progesterone or estradiol production, and on mitochondrial health, by evaluating mitochondrial activity as well as mtDNA content. Neither MPB nor BPB showed any effect over progesterone production or the expression of genes controlling steroid production. Only BPB affected the mitochondria, decreasing mtDNA content at supraphysiological concentrations (1000 nM). Prolonged exposure to these compounds produced no effects in neither of these parameters. In conclusion, neither MPB nor BPB significantly affected basal steroidogenesis in granulosa cells. Although evidence supporting paraben toxicity is prevalent, here we put forth evidence that suggests that parabens do not affect basal steroidogenesis in human granulosa cells.


Assuntos
Disruptores Endócrinos/toxicidade , Células da Granulosa/efeitos dos fármacos , Parabenos/toxicidade , Progesterona/biossíntese , Adulto , Aromatase/genética , Líquidos Corporais/química , Células Cultivadas , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , DNA Mitocondrial/metabolismo , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Disruptores Endócrinos/análise , Estradiol Desidrogenases/genética , Feminino , Células da Granulosa/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Complexos Multienzimáticos/genética , Parabenos/administração & dosagem , Parabenos/análise , Cultura Primária de Células , Progesterona Redutase/genética , Esteroide Isomerases/genética
8.
Neurochem Res ; 45(6): 1365-1374, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31363896

RESUMO

Glutamate is the major excitatory amino acid neurotransmitter in the vertebrate brain. It exerts its actions through the activation of specific plasma membrane receptors expressed in neurons and glial cells. Overactivation of glutamate receptors results in neuronal death, known as excitotoxicity. A family of sodium-dependent glutamate transporters enriched in glial cells are responsible of the vast majority of the removal of this amino acid form the synaptic cleft. Therefore, a precise and exquisite regulation of these proteins is required not only for a proper glutamatergic transmission but also for the prevention of an excitotoxic insult. Manganese is a trace element essential as a cofactor for several enzymatic systems, although in high concentrations is involved in the disruption of brain glutamate homeostasis. The molecular mechanisms associated to manganese neurotoxicity have been focused on mitochondrial function, although energy depletion severely compromises the glutamate uptake process. In this context, in this contribution we analyze the effect of manganese exposure in glial glutamate transporters function. To this end, we used the well-established model of chick cerebellar Bergmann glia cultures. A time and dose dependent modulation of [3H]-D-aspartate uptake was found. An increase in the transporter catalytic efficiency, most probably linked to a discrete increase in the affinity of the transporter was detected upon manganese exposure. Interestingly, glucose uptake was reduced by this metal. These results favor the notion of a direct effect of manganese on glial cells, this in turn alters their coupling with neurons and might lead to changes in glutamatergic transmission.


Assuntos
Transportador 1 de Aminoácido Excitatório/metabolismo , Manganês/administração & dosagem , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Animais , Ácido Aspártico/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga
9.
Mol Neurobiol ; 55(6): 5202-5209, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28875233

RESUMO

Glutamate is the major excitatory transmitter of the vertebrate brain. It exerts its actions through the activation of specific plasma membrane receptors expressed both in neurons and in glial cells. Recent evidence has shown that glutamate uptake systems, particularly enriched in glia cells, trigger biochemical cascades in a similar fashion as receptors. A tight regulation of glutamate extracellular levels prevents neuronal overstimulation and cell death, and it is critically involved in glutamate turnover. Glial glutamate transporters are responsible of the majority of the brain glutamate uptake activity. Once internalized, this excitatory amino acid is rapidly metabolized to glutamine via the astrocyte-enriched enzyme glutamine synthetase. A coupling between glutamate uptake and glutamine synthesis and release has been commonly known as the glutamate/glutamine shuttle. Taking advantage of the established model of cultured Bergmann glia cells, in this contribution, we explored the gene expression regulation of glutamine synthetase. A time- and dose-dependent regulation of glutamine synthetase protein and activity levels was found. Moreover, glutamate exposure resulted in the transient shift of glutamine synthetase mRNA from the monosomal to the polysomal fraction. These results demonstrate a novel mode of glutamate-dependent glutamine synthetase regulation and strengthen the notion of an exquisite glia neuronal interaction in glutamatergic synapses.


Assuntos
Glutamato-Amônia Ligase/metabolismo , Ácido Glutâmico/metabolismo , Neuroglia/enzimologia , Biossíntese de Proteínas , Animais , Células Cultivadas , Embrião de Galinha , Glutamato-Amônia Ligase/genética , Modelos Biológicos , Polirribossomos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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