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1.
Chaos ; 34(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775681

RESUMO

We consider a heterogeneous, globally coupled population of excitatory quadratic integrate-and-fire neurons with excitability adaptation due to a metabolic feedback associated with ketogenic diet, a form of therapy for epilepsy. Bifurcation analysis of a three-dimensional mean-field system derived in the framework of next-generation neural mass models allows us to explain the scenarios and suggest control strategies for the transitions between the neurophysiologically desired asynchronous states and the synchronous, seizure-like states featuring collective oscillations. We reveal two qualitatively different scenarios for the onset of synchrony. For weaker couplings, a bistability region between the lower- and the higher-activity asynchronous states unfolds from the cusp point, and the collective oscillations emerge via a supercritical Hopf bifurcation. For stronger couplings, one finds seven co-dimension two bifurcation points, including pairs of Bogdanov-Takens and generalized Hopf points, such that both lower- and higher-activity asynchronous states undergo transitions to collective oscillations, with hysteresis and jump-like behavior observed in vicinity of subcritical Hopf bifurcations. We demonstrate three control mechanisms for switching between asynchronous and synchronous states, involving parametric perturbation of the adenosine triphosphate (ATP) production rate, external stimulation currents, or pulse-like ATP shocks, and indicate a potential therapeutic advantage of hysteretic scenarios.


Assuntos
Adaptação Fisiológica , Dieta Cetogênica , Modelos Neurológicos , Neurônios , Convulsões , Neurônios/metabolismo , Convulsões/fisiopatologia , Humanos , Trifosfato de Adenosina/metabolismo
2.
Sci Adv ; 10(20): eado1463, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758782

RESUMO

A ketogenic diet (KD) is a high-fat, low-carbohydrate diet that leads to the generation of ketones. While KDs improve certain health conditions and are popular for weight loss, detrimental effects have also been reported. Here, we show mice on two different KDs and, at different ages, induce cellular senescence in multiple organs, including the heart and kidney. This effect is mediated through adenosine monophosphate-activated protein kinase (AMPK) and inactivation of mouse double minute 2 (MDM2) by caspase-2, leading to p53 accumulation and p21 induction. This was established using p53 and caspase-2 knockout mice and inhibitors to AMPK, p21, and caspase-2. In addition, senescence-associated secretory phenotype biomarkers were elevated in serum from mice on a KD and in plasma samples from patients on a KD clinical trial. Cellular senescence was eliminated by a senolytic and prevented by an intermittent KD. These results have important clinical implications, suggesting that the effects of a KD are contextual and likely require individual optimization.


Assuntos
Senescência Celular , Dieta Cetogênica , Camundongos Knockout , Proteína Supressora de Tumor p53 , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Camundongos , Humanos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Masculino , Especificidade de Órgãos
3.
Nutrients ; 16(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732505

RESUMO

Epilepsy is one of the most disabling neurological diseases. Despite proper pharmacotherapy and the availability of 2nd and 3rd generation antiepileptic drugs, deep brain stimulation, and surgery, up to 30-40% of epilepsy patients remain drug-resistant. Consequences of this phenomenon include not only decreased a quality of life, and cognitive, behavioral, and personal disorders, but also an increased risk of death, i.e., in the mechanism of sudden unexpected death in epilepsy patients (SUDEP). The main goals of epilepsy treatment include three basic issues: achieving the best possible seizure control, avoiding the undesired effects of treatment, and maintaining/improving the quality of patients' lives. Therefore, numerous attempts are made to offer alternative treatments for drug-resistant seizures, an example of which is the ketogenic diet. It is a long-known but rarely used dietary therapy for intractable seizures. One of the reasons for this is the unpalatability of the classic ketogenic diet, which reduces patient compliance and adherence rates. However, its antiseizure effects are often considered to be worth the effort. Until recently, the diet was considered the last-resort treatment. Currently, it is believed that a ketogenic diet should be used much earlier in patients with well-defined indications. In correctly qualified patients, seizure activity may be reduced by over 90% or even abolished for long periods after the diet is stopped. A ketogenic diet can be used in all age groups, although most of the available literature addresses pediatric epilepsy. In this article, we focus on the mechanisms of action, effectiveness, and adverse effects of different variants of the ketogenic diet, including its classic version, a medium-chain triglyceride diet, a modified Atkins diet, and a low glycemic index treatment.


Assuntos
Dieta Cetogênica , Epilepsia , Dieta Cetogênica/métodos , Humanos , Epilepsia/dietoterapia , Resultado do Tratamento , Epilepsia Resistente a Medicamentos/dietoterapia , Qualidade de Vida , Anticonvulsivantes/uso terapêutico , Anticonvulsivantes/administração & dosagem , Criança
4.
Nutrients ; 16(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732595

RESUMO

While ketogenic diets (KDs) may have potential as adjunct treatments for gastrointestinal diseases, there is little knowledge on how the fat source of these diets impacts intestinal health. The objective of this study was to investigate how the source of dietary fat of KD influences experimental colitis. We fed nine-week-old male C57BL/6J mice (n = 36) with a low-fat control diet or KD high either in saturated fatty acids (SFA-KD) or polyunsaturated linoleic acid (LA-KD) for four weeks and then induced colitis with dextran sodium sulfate (DSS). To compare the diets, we analyzed macroscopic and histological changes in the colon, intestinal permeability to fluorescein isothiocyanate-dextran (FITC-dextran), and the colonic expression of tight junction proteins and inflammatory markers. While the effects were more pronounced with LA-KD, both KDs markedly alleviated DSS-induced histological lesions. LA-KD prevented inflammation-related weight loss and the shortening of the colon, as well as preserved Il1b and Tnf expression at a healthy level. Despite no significant between-group differences in permeability to FITC-dextran, LA-KD mitigated changes in tight junction protein expression. Thus, KDs may have preventive potential against intestinal inflammation, with the level of the effect being dependent on the dietary fat source.


Assuntos
Colite , Colo , Sulfato de Dextrana , Dieta Cetogênica , Gorduras na Dieta , Modelos Animais de Doenças , Fluoresceína-5-Isotiocianato/análogos & derivados , Camundongos Endogâmicos C57BL , Animais , Colite/induzido quimicamente , Colite/dietoterapia , Masculino , Camundongos , Gorduras na Dieta/efeitos adversos , Colo/patologia , Colo/metabolismo , Permeabilidade , Proteínas de Junções Íntimas/metabolismo , Interleucina-1beta/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ácidos Graxos , Dextranos
5.
Nutrients ; 16(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612972

RESUMO

Polycystic ovary syndrome (PCOS) is a multifaceted and heterogeneous disorder, linked with notable reproductive, metabolic, and psychological outcomes. During adolescence, key components of PCOS treatment involve weight loss achieved through lifestyle and dietary interventions, subsequently pursued by pharmacological or surgical therapies. Nutritional interventions represent the first-line therapeutic approach in adolescents affected by PCOS, but different kinds of dietary protocols exist, so it is necessary to clarify the effectiveness and benefits of the most well-known nutritional approaches. We provided a comprehensive review of the current literature concerning PCOS definition, pathophysiology, and treatment options, highlighting nutritional strategies, particularly those related to high-fat diets. The high-fat nutritional protocols proposed in the literature, such as the ketogenic diet (KD), appear to provide benefits to patients with PCOS in terms of weight loss and control of metabolic parameters. Among the different types of KD studies, very low-calorie ketogenic diets (VLCKD), can be considered an effective dietary intervention for the short-term treatment of patients with PCOS. It rapidly leads to weight loss alongside improvements in body composition and metabolic profile. Even though extremely advantageous, long-term adherence to the KD is a limiting factor. Indeed, this dietary regimen could become unsustainable due to the important restrictions required for ketosis development. Thus, a combination of high-fat diets with more nutrient-rich nutritional regimens, such as the Mediterranean diet, can amplify positive effects for individuals with PCOS.


Assuntos
Dieta Cetogênica , Síndrome do Ovário Policístico , Feminino , Adolescente , Humanos , Dieta Hiperlipídica , Síndrome do Ovário Policístico/terapia , Composição Corporal , Redução de Peso
6.
Nutr Diabetes ; 14(1): 18, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609395

RESUMO

BACKGROUND: The effectiveness of ketogenic diet (KD) in ameliorating fatty liver has been established, although its mechanism is under investigation. Fibroblast growth factor 21 (FGF21) positively regulates obesity-associated metabolic disorders and is elevated by KD. FGF21 conventionally initiates its intracellular signaling via receptor ß-klotho (KLB). However, the mechanistic role of FGF21-KLB signaling for KD-ameliorated fatty liver remains unknown. This study aimed to delineate the critical role of FGF21 signaling in the ameliorative effects of KD on hepatic steatosis. METHODS: Eight-week-old C57BL/6 J mice were fed a chow diet (CD), a high-fat diet (HFD), or a KD for 16 weeks. Adeno-associated virus-mediated liver-specific KLB knockdown mice and control mice were fed a KD for 16 weeks. Phenotypic assessments were conducted during and after the intervention. We investigated the mechanism underlying KD-alleviated hepatic steatosis using multi-omics and validated the expression of key genes. RESULTS: KD improved hepatic steatosis by upregulating fatty acid oxidation and downregulating lipogenesis. Transcriptional analysis revealed that KD dramatically activated FGF21 pathway, including KLB and fibroblast growth factor receptor 1 (FGFR1). Impairing liver FGF21 signaling via KLB knockdown diminished the beneficial effects of KD on ameliorating fatty liver, insulin resistance, and regulating lipid metabolism. CONCLUSION: KD demonstrates beneficial effects on diet-induced metabolic disorders, particularly on hepatic steatosis. Liver FGF21-KLB signaling plays a critical role in the KD-induced amelioration of hepatic steatosis.


Assuntos
Dieta Cetogênica , Fígado Gorduroso , Fatores de Crescimento de Fibroblastos , Resistência à Insulina , Animais , Camundongos , Camundongos Endogâmicos C57BL
7.
Cancer Res ; 84(10): 1597-1612, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38588411

RESUMO

Resistance to immune checkpoint blockade (ICB) therapy represents a formidable clinical challenge limiting the efficacy of immunotherapy. In particular, prostate cancer poses a challenge for ICB therapy due to its immunosuppressive features. A ketogenic diet (KD) has been reported to enhance response to ICB therapy in some other cancer models. However, adverse effects associated with continuous KD were also observed, demanding better mechanistic understanding and optimized regimens for using KD as an immunotherapy sensitizer. In this study, we established a series of ICB-resistant prostate cancer cell lines and developed a highly effective strategy of combining anti-PD1 and anti-CTLA4 antibodies with histone deacetylase inhibitor (HDACi) vorinostat, a cyclic KD (CKD), or dietary supplementation of the ketone body ß-hydroxybutyrate (BHB), which is an endogenous HDACi. CKD and BHB supplementation each delayed prostate cancer tumor growth as monotherapy, and both BHB and adaptive immunity were required for the antitumor activity of CKD. Single-cell transcriptomic and proteomic profiling revealed that HDACi and ketogenesis enhanced ICB efficacy through both cancer cell-intrinsic mechanisms, including upregulation of MHC class I molecules, and -extrinsic mechanisms, such as CD8+ T-cell chemoattraction, M1/M2 macrophage rebalancing, monocyte differentiation toward antigen-presenting cells, and diminished neutrophil infiltration. Overall, these findings illuminate a potential clinical path of using HDACi and optimized KD regimens to enhance ICB therapy for prostate cancer. SIGNIFICANCE: Optimized cyclic ketogenic diet and 1,3-butanediol supplementation regimens enhance the efficacy of immune checkpoint blockade in prostate cancer through epigenetic and immune modulations, providing dietary interventions to sensitize tumors to immunotherapy.


Assuntos
Dieta Cetogênica , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Inibidores de Checkpoint Imunológico , Neoplasias da Próstata , Masculino , Dieta Cetogênica/métodos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/dietoterapia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Camundongos , Epigênese Genética/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Vorinostat/farmacologia , Vorinostat/uso terapêutico , Vorinostat/administração & dosagem , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Ácido 3-Hidroxibutírico , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores
8.
Metab Brain Dis ; 39(4): 635-648, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429463

RESUMO

Obesity results from an energy imbalance and has been considered an epidemic due to its increasing rates worldwide. It is classified as a low-grade chronic inflammatory disease and has associated comorbidities. Different nutritional strategies are used for the purpose of weight loss, highlighting low-carbohydrate (LC) diets, ketogenic diets, and intermittent fasting (IF). These strategies can lead to metabolic and behavioral changes as they stimulate different biochemical pathways. Therefore, this study evaluated memory, energy metabolism, neuroinflammation, oxidative stress, and antioxidant defense parameters in mice subjected to an LC diet, ketogenic diet (KD), or IF. Eighty male Swiss mice, 60 days old, were divided into 4 groups: control, LC, KD, or IF. Body weight was measured weekly, and food intake every 48 h. After 15 days of nutritional interventions, the animals were subjected to the behavioral object recognition test and subsequently euthanized. Then, visceral fat was removed and weighed, and the brain was isolated for inflammatory and biochemical analysis. We concluded from this study that the LC and KD strategies could damage memory, IF improves the production of adenosine triphosphate (ATP), and the LC, KD, and IF strategies do not lead to neuroinflammatory damage but present damage at the level of oxidative stress.


Assuntos
Dieta Cetogênica , Estresse Oxidativo , Animais , Masculino , Camundongos , Estresse Oxidativo/fisiologia , Transtornos da Memória/metabolismo , Transtornos da Memória/etiologia , Doenças Neuroinflamatórias/metabolismo , Dieta com Restrição de Carboidratos , Jejum/metabolismo , Metabolismo Energético/fisiologia , Encéfalo/metabolismo
9.
Sci Rep ; 14(1): 5610, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453966

RESUMO

Given that ketogenic diets (KDs) are extremely high in dietary fat, we compared different fats in KDs to determine which was the best for cancer prevention. Specifically, we compared a Western and a 15% carbohydrate diet to seven different KDs, containing either Western fats or fats enriched in medium chain fatty acids (MCTs), milk fat (MF), palm oil (PO), olive oil (OO), corn oil (CO) or fish oil (FO) for their ability to reduce nicotine-derived nitrosamine ketone (NNK)-induced lung cancer in mice. While all the KDs tested were more effective at reducing lung nodules than the Western or 15% carbohydrate diet, the FO-KD was most effective at reducing lung nodules. Correlating with this, mice on the FO-KD had low blood glucose and the highest ß-hydroxybutyrate level, lowest liver fatty acid synthase/carnitine palmitoyl-1a ratio and a dramatic increase in fecal Akkermansia. We found no liver damage induced by the FO-KD, while the ratio of total cholesterol/HDL was unchanged on the different diets. We conclude that a FO-KD is superior to KDs enriched in other fats in reducing NNK-induced lung cancer, perhaps by being the most effective at skewing whole-body metabolism from a dependence on glucose to fats as an energy source.


Assuntos
Dieta Cetogênica , Gorduras Insaturadas na Dieta , Neoplasias Pulmonares , Camundongos , Animais , Óleos de Peixe/farmacologia , Óleos de Peixe/metabolismo , Gorduras Insaturadas na Dieta/metabolismo , Óleos de Plantas/farmacologia , Óleos de Plantas/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/prevenção & controle , Gorduras na Dieta/metabolismo , Azeite de Oliva , Dieta , Carboidratos
10.
Signal Transduct Target Ther ; 9(1): 59, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462638

RESUMO

Diet, serving as a vital source of nutrients, exerts a profound influence on human health and disease progression. Recently, dietary interventions have emerged as promising adjunctive treatment strategies not only for cancer but also for neurodegenerative diseases, autoimmune diseases, cardiovascular diseases, and metabolic disorders. These interventions have demonstrated substantial potential in modulating metabolism, disease trajectory, and therapeutic responses. Metabolic reprogramming is a hallmark of malignant progression, and a deeper understanding of this phenomenon in tumors and its effects on immune regulation is a significant challenge that impedes cancer eradication. Dietary intake, as a key environmental factor, can influence tumor metabolism. Emerging evidence indicates that dietary interventions might affect the nutrient availability in tumors, thereby increasing the efficacy of cancer treatments. However, the intricate interplay between dietary interventions and the pathogenesis of cancer and other diseases is complex. Despite encouraging results, the mechanisms underlying diet-based therapeutic strategies remain largely unexplored, often resulting in underutilization in disease management. In this review, we aim to illuminate the potential effects of various dietary interventions, including calorie restriction, fasting-mimicking diet, ketogenic diet, protein restriction diet, high-salt diet, high-fat diet, and high-fiber diet, on cancer and the aforementioned diseases. We explore the multifaceted impacts of these dietary interventions, encompassing their immunomodulatory effects, other biological impacts, and underlying molecular mechanisms. This review offers valuable insights into the potential application of these dietary interventions as adjunctive therapies in disease management.


Assuntos
Dieta Cetogênica , Neoplasias , Humanos , Restrição Calórica , Dieta , Jejum , Neoplasias/terapia
11.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38473723

RESUMO

The effect of different diet patterns on psoriasis (PSO) and psoriatic arthritis (PSA) is unknown. Τhe aim of our study was to evaluate the effectiveness of a Mediterranean diet (MD) and Ketogenic diet (KD), in patients with PSO and PSA. Twenty-six patients were randomly assigned to start either with MD or KD for a period of 8 weeks. After a 6-week washout interval, the two groups were crossed over to the other type of diet for 8 weeks. At the end of this study, MD and KD resulted in significant reduction in weight (p = 0.002, p < 0.001, respectively), in BMI (p = 0.006, p < 0.001, respectively), in waist circumference (WC) (p = 0.001, p < 0.001, respectively), in total fat mass (p = 0.007, p < 0.001, respectively), and in visceral fat (p = 0.01, p < 0.001, respectively), in comparison with baseline. After KD, patients displayed a significant reduction in the Psoriasis Area and Severity Index (PASI) (p = 0.04), Disease Activity Index of Psoriatic Arthritis (DAPSA) (p = 0.004), interleukin (IL)-6 (p = 0.047), IL-17 (p = 0.042), and IL-23 (p = 0.037), whereas no significant differences were observed in these markers after MD (p > 0.05), compared to baseline. The 22-week MD-KD diet program in patients with PSO and PSA led to beneficial results in markers of inflammation and disease activity, which were mainly attributed to KD.


Assuntos
Artrite Psoriásica , Dieta Cetogênica , Dieta Mediterrânea , Psoríase , Humanos , Estudos Cross-Over , Inflamação , Obesidade , Biomarcadores
12.
Crit Rev Oncol Hematol ; 196: 104264, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341120

RESUMO

The effect of calorie restriction, fasting, and ketogenic diets on the treatment of liver cancer remains uncertain. Therefore, we conducted a systematic review to evaluate the effect of restrictive diets on the development and progression of liver cancer in animal models. We did a meta-analysis using the Cochrane Collaboration's Review Manager software, with the random effects model and the inverse variance technique. We examined 19 studies that were conducted between 1983 and 2020. Of these, 63.2% investigated calorie restriction, 21.0% experimented with a ketogenic diet, and 15.8% investigated the effects of fasting. The intervention lasted anything from 48 h to 221 weeks. Results showed that restrictive diets may reduce tumor incidence and progression, with a significant reduction in the risk of liver cancer development. Thereby, our results suggest that putting limits on what you eat may help treat liver cancer in more ways than one.


Assuntos
Dieta Cetogênica , Neoplasias Hepáticas , Animais , Humanos , Dieta Cetogênica/métodos , Restrição Calórica , Jejum , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle
13.
Biochem Biophys Res Commun ; 702: 149559, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38341923

RESUMO

OBJECTIVE: Ketogenic diets (KD) have been shown to alleviate insulin resistance (IR) by exerting anti-lipogenic and insulin sensitizing effects in the liver through a variety of pathways. The present study sought to investigate whether a ketogenic diet also improves insulin sensitization in skeletal muscle cells through alleviating endoplasmic reticulum stress. METHODS: High-fat diet-induced IR mice were allowed to a 2-week ketogenic diet. Insulin resistance and glucose tolerance were evaluated through GTT, ITT, and HOMA-IR. The C2C12 myoblasts exposed to palmitic acid were used to evaluate the insulin sensitization effects of ß-hydroxybutyric acid (ß-OHB). Molecular mechanisms concerning ER stress signaling activation and glucose uptake were assessed. RESULTS: The AKT/GSK3ß pathway was inhibited, ER stress signaling associated with IRE1, PERK, and BIP was activated, and the number of Glut4 proteins translocated to membrane decreased in the muscle of HFD mice. However, all these changes were reversed after 2 weeks of feeding on a ketogenic diet. Consistently in C2C12 myoblasts, the AKT/GSK3ß pathway was inhibited by palmitic acid (PA) treatment. The endoplasmic reticulum stress-related proteins, IRE1, and BIP were increased, and the number of Glut4 proteins on the cell membrane decreased. However, ß-OHB treatment alleviated ER stress and improved the glucose uptake of C2C12 cells. CONCLUSION: Our data reveal that KD ameliorated HFD-induced insulin resistance in skeletal muscle, which was partially mediated by inhibiting endoplasmic reticulum stress. The insulin sensitization effect of ß-OHB is associated with up regulation of AKT/GSK3ß pathway and the increase in the number of Glut4 proteins on the cell membrane.


Assuntos
Dieta Cetogênica , Resistência à Insulina , Camundongos , Animais , Resistência à Insulina/fisiologia , Dieta Hiperlipídica/efeitos adversos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ácido Palmítico/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Estresse do Retículo Endoplasmático , Insulina/metabolismo , Músculo Esquelético/metabolismo , Glucose/metabolismo , Camundongos Endogâmicos C57BL
14.
J Orthop Surg Res ; 19(1): 127, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326818

RESUMO

BACKGROUND: Icariin, a traditional Chinese medicine, has demonstrated anti-osteoporotic properties in ovariectomized mice. However, its effectiveness in preventing bone loss induced by ketogenic diet (KD), which mimics osteoporosis in human, remains unexplored. This study aims to investigate icariin's impact on KD-induced bone loss in mice. METHODS: Thirty mice were divided into: sham, KD, and KD + icariin groups. Post a 12-week intervention, evaluation including bone microstructures, serum concentrations of tartrate-resistant acid phosphatase (TRAP) and bone-specific alkaline phosphatase (ALP), and femoral tissue expression levels of osteocalcin (OCN) and TRAP. The expression levels of mammalian target of rapamycin (mTOR), ALP, peroxisome proliferator-activated receptor gamma (PPAR-γ), phosphorylated mTOR (p-mTOR), and the autophagy adaptor protein (p62) were also analyzed. Alizarin granule deposition and cellular ALP levels were measured following the induction of bone marrow mesenchymal stem cells (BMSCs) into osteogenesis. RESULTS: The study found that KD significantly impaired BMSCs' osteogenic differentiation, leading to bone loss. Icariin notably increased bone mass, stimulated osteogenesis, and reduced cancellous bone loss. In the KD + icariin group, measures such as bone tissue density (TMD), bone volume fraction (BV/TV), trabecular number (Tb.N), and trabecular thickness (Tb.Th) were significantly higher than in the KD group. Additionally, bone trabecular separation (Tb.Sp) was markedly lower in the KD + icariin group. Moreover, icariin increased OCN and ALP levels while suppressing PPAR-γ, TRAP, p62, and p-mTOR. In cellular studies, icariin encouraged osteogenic development in BMSCs under KD conditions. CONCLUSIONS: Icariin effectively counteracts bone thinning and improves bone microstructure. Its mechanism likely involves stimulating BMSCs osteogenic differentiation and inhibiting bone resorption, potentially through mTOR downregulation. These findings suggest icariin's potential as an alternative treatment for KD-induced bone loss.


Assuntos
Doenças Ósseas Metabólicas , Dieta Cetogênica , Flavonoides , Células-Tronco Mesenquimais , Osteoporose , Humanos , Camundongos , Animais , Osteogênese , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/farmacologia , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Diferenciação Celular , Doenças Ósseas Metabólicas/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Células-Tronco Mesenquimais/metabolismo , Células da Medula Óssea/metabolismo , Células Cultivadas , Mamíferos
15.
PLoS One ; 19(1): e0296523, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166036

RESUMO

PURPOSE: Ketogenic diets may positively influence cancer through pleiotropic mechanisms, but only a few small and short-term studies have addressed feasibility and efficacy in cancer patients. The primary goals of this study were to evaluate the feasibility and the sustained metabolic effects of a personalized well-formulated ketogenic diet (WFKD) designed to achieve consistent blood beta-hydroxybutyrate (ßHB) >0.5 mM in women diagnosed with stage IV metastatic breast cancer (MBC) undergoing chemotherapy. METHODS: Women (n = 20) were enrolled in a six month, two-phase, single-arm WFKD intervention (NCT03535701). Phase I was a highly-supervised, ad libitum, personalized WFKD, where women were provided with ketogenic-appropriate food daily for three months. Phase II transitioned women to a self-administered WFKD with ongoing coaching for an additional three months. Fasting capillary ßHB and glucose were collected daily; weight, body composition, plasma insulin, and insulin resistance were collected at baseline, three and six months. RESULTS: Capillary ßHB indicated women achieved nutritional ketosis (Phase I mean: 0.8 mM (n = 15); Phase II mean: 0.7 mM (n = 9)). Body weight decreased 10% after three months, primarily from body fat. Fasting plasma glucose, plasma insulin, and insulin resistance also decreased significantly after three months (p < 0.01), an effect that persisted at six months. CONCLUSIONS: Women diagnosed with MBC undergoing chemotherapy can safely achieve and maintain nutritional ketosis, while improving body composition and insulin resistance, out to six months.


Assuntos
Neoplasias da Mama , Dieta Cetogênica , Resistência à Insulina , Insulinas , Cetose , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Estudos de Viabilidade , Ácido 3-Hidroxibutírico
16.
Int J Vitam Nutr Res ; 94(1): 1-9, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36755497

RESUMO

In the last few years, numerous studies have demonstrated that dietary modifications in the form of calory restriction exert beneficial effects in several clinical entities, including aging-related pathologies, autoimmune diseases and cancer. Both as preventive but also as therapeutic modalities, these dietary regimens can impact systemic metabolism, immune and hormonal responses, redox balance and gut microbiota, among others. In the field of oncology, the vast majority of experimental work has explored the role of restricted diets in the prevention of malignant tumors, mostly in carcinogenesis-induced models, with at least encouraging results; on the contrary, less research has been performed in the management of full-blown cancer with ketogenic diet or caloric restriction protocols. Herein, we are aiming to review the relevant preclinical and clinical studies to date that investigate the role of caloric restriction in the treatment of established cancer.


Assuntos
Dieta Cetogênica , Neoplasias , Animais , Restrição Calórica , Neoplasias/terapia , Dieta , Carcinogênese
17.
J Anim Physiol Anim Nutr (Berl) ; 108(2): 541-556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38091342

RESUMO

Ketogenic diets (KD) have been used in the treatment of epilepsy in humans for around a century and, more recently, they have been implanted for cancer patients, as well as in the treatment of obesity. This type of diet consists of high-fat levels, an adequate amount of protein and restricted carbohydrates, or high medium-chain triglycerides. Recently, the ketogenic diet has gained attention in veterinary medicine and studies were published evaluating the effects of KD in dogs with epilepsy. The objective of this review was to highlight recent studies about the application of KD in dogs and cats, to describe the neurobiochemical mechanisms through which KD improves epilepsy crisis, and their adverse effects. Studies were identified by a systematic review of literature available on PubMed, Embase, and Scopus. All cohort and case-control studies were included, and all articles were exported to Mendeley® citation manager, and duplicates were automatically removed. Seven articles and three conference abstracts conducted with dogs were included in the present study. There is evidence that the consumption of diets with medium-chain triglycerides increases the concentration of circulating ketone bodies and improves epilepsy signs, although these diets have higher carbohydrate and lower fat content when compared to the classic KD.


Assuntos
Doenças do Gato , Dieta Cetogênica , Doenças do Cão , Epilepsia , Humanos , Gatos , Cães , Animais , Dieta Cetogênica/efeitos adversos , Dieta Cetogênica/veterinária , Epilepsia/veterinária , Triglicerídeos/metabolismo
18.
Biomed J ; 47(1): 100609, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37245566

RESUMO

BACKGROUND: Ketogenic diets (KDs) are high-fat diets with putative anti-tumor effects. The aim of this study was to synthesize the evidence for the anti-tumor effects of KDs in mice, with a focus on their possible synergism with chemotherapy (CT), radiotherapy (RT), or targeted therapies (TT). METHODS: Relevant studies were retrieved from a literature search. A total of 43 articles reporting on 65 mouse experiments fulfilled the inclusion criteria, and 1755 individual mouse survival times were collated from the study authors or the publications. The restricted mean survival time ratio (RMSTR) between the KD and control groups served as the effect size. Bayesian evidence synthesis models were used to estimate pooled effect sizes and to assess the impact of putative confounders and synergism between KD and other therapies. RESULTS: Overall, there was a significant survival-prolonging effect of KD monotherapy (RMSTR = 1.161 ± 0.040), which was confirmed in meta-regression accounting for syngeneic versus xenogeneic models, early versus late KD start and subcutaneous versus other organ growth. Combining the KD with RT or TT, but not CT, was associated with a further 30% (RT) or 21% (TT) prolongation of survival. An analysis accounting for 15 individual tumor entities showed that KDs exerted significant survival-prolonging effects in pancreatic cancer (all treatment combinations), gliomas (KD + RT and KD + TT), head and neck cancer (KD + RT), and stomach cancer (KD+RT and KD + TT). CONCLUSIONS: This analytical study confirmed the overall anti-tumor effects of KDs in a large number of mouse experiments and provides evidence for synergistic effects with RT and TT.


Assuntos
Dieta Cetogênica , Neoplasias , Camundongos , Animais , Teorema de Bayes , Dieta Hiperlipídica
19.
Obes Surg ; 34(1): 236-249, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052747

RESUMO

Previous studies investigated low-calorie diets (LCD), very-low-calorie diets (VLCD), and very-low-calorie ketogenic diets (VLCKD) in relation to weight loss and outcomes for bariatric surgery patients. However, the overall effects of these diets on various outcomes remain unclear. This study aimed to assess the impact of preoperative restricted calorie diets on weight, body mass index (BMI), operation time (OT), and hospital stay (HS) in bariatric surgery patients. Seventeen articles were analyzed, revealing the highest weight loss (-8.62) and BMI reduction (-5.75) with VLCKD. Due to insufficient data, the impact of these diets on OT and HS could not be determined. Further interventional studies are required to determine the ideal preoperative diet that achieves optimal weight loss, patient compliance, tolerance, acceptance, and surgical outcomes.


Assuntos
Cirurgia Bariátrica , Dieta Cetogênica , Obesidade Mórbida , Humanos , Índice de Massa Corporal , Obesidade Mórbida/cirurgia , Tempo de Internação , Restrição Calórica , Redução de Peso
20.
Epilepsy Behav ; 150: 109535, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118233

RESUMO

AIM: To evaluate the effectiveness of the ketogenic diet treatment in a cohort of patients with drug-resistant epilepsy with a mutation in the DEPDC5 gene. MATERIALS AND METHODS: We followed four paediatric patients with drug resistant DEPDC5-related epilepsy through a ketogenic diet (KD) treatment course. We analyzed the following parameters of their clinical profiles: past medical history, clinical characteristics of seizure morphology, EEG records pre- and post-KD treatment, the results of MRI head and neurological and psychological examinations (pre-treatment and throughout treatment course). We evaluated the effectiveness of previous therapeutic approaches and the current treatment with ketogenic diet alongside results of neuroimaging studies. Effect of KD on co-morbid behavioural and psychiatric symptoms, as well as adverse effects from KD were also assessed. RESULTS: In three patients, the introduction of the ketogenic diet resulted in the cessation of seizures, while in 1 patient with co-morbid cortical dysplasia, epileptic seizures of lesser severity returned after an initial seizure-free period of several weeks. Further, 1 patient was able to transition to a KD-only treatment regimen. The remaining patients were able to reduce the number of antiseizure medicine (ASM) to a monotherapy. In all cases we observed improvements in EEG results. Our cohort included one patient whose MRI head showed cortical dysplasia. However, no patients demonstrated any neurological signs in neurological examination. Psychological examination showed normal intellectual development in all patients, although behavioral disorders and difficulties at school were observed. The introduction of KD treatment correlated with improvement in school performance and improved behavioral regulation. No clinically significant adverse events were observed. CONCLUSIONS: KD seems to be both effective and well tolerated in young patients with DEPDC5-related epilepsy, both as a monotherapy and as an adjunct to ASM. We recommend an early adoption of this therapeutic approach in this patient demographic. Our results demonstrate that the positive effects of KD treatment encompass improvements in general functioning, particularly in the context of school performance and behavior, in addition to the achievement of good seizure control.


Assuntos
Dieta Cetogênica , Epilepsia Resistente a Medicamentos , Epilepsia , Malformações do Desenvolvimento Cortical , Criança , Humanos , Dieta Cetogênica/métodos , Resultado do Tratamento , Estudos Retrospectivos , Convulsões
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