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1.
Int J Mol Sci ; 24(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37958602

RESUMO

Most studies on ketosis have focused on short-term effects, male athletes, or weight loss. Hereby, we studied the effects of short-term ketosis suppression in healthy women on long-standing ketosis. Ten lean (BMI 20.5 ± 1.4), metabolically healthy, pre-menopausal women (age 32.3 ± 8.9) maintaining nutritional ketosis (NK) for > 1 year (3.9 years ± 2.3) underwent three 21-day phases: nutritional ketosis (NK; P1), suppressed ketosis (SuK; P2), and returned to NK (P3). Adherence to each phase was confirmed with daily capillary D-beta-hydroxybutyrate (BHB) tests (P1 = 1.9 ± 0.7; P2 = 0.1 ± 0.1; and P3 = 1.9 ± 0.6 pmol/L). Ageing biomarkers and anthropometrics were evaluated at the end of each phase. Ketosis suppression significantly increased: insulin, 1.78-fold from 33.60 (± 8.63) to 59.80 (± 14.69) pmol/L (p = 0.0002); IGF1, 1.83-fold from 149.30 (± 32.96) to 273.40 (± 85.66) µg/L (p = 0.0045); glucose, 1.17-fold from 78.6 (± 9.5) to 92.2 (± 10.6) mg/dL (p = 0.0088); respiratory quotient (RQ), 1.09-fold 0.66 (± 0.05) to 0.72 (± 0.06; p = 0.0427); and PAI-1, 13.34 (± 6.85) to 16.69 (± 6.26) ng/mL (p = 0.0428). VEGF, EGF, and monocyte chemotactic protein also significantly increased, indicating a pro-inflammatory shift. Sustained ketosis showed no adverse health effects, and may mitigate hyperinsulinemia without impairing metabolic flexibility in metabolically healthy women.


Assuntos
Doenças dos Bovinos , Dieta Cetogênica , Hiperinsulinismo , Cetose , Animais , Bovinos , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Doenças dos Bovinos/metabolismo , Insulina/farmacologia , Ácido 3-Hidroxibutírico/metabolismo
2.
Antioxidants (Basel) ; 12(9)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37760052

RESUMO

In the pursuit of longevity and healthspan, we are challenged with first overcoming chronic diseases of ageing: cardiovascular disease, hypertension, cancer, dementias, type 2 diabetes mellitus. These are hyperinsulinaemia diseases presented in different tissue types. Hyperinsulinaemia reduces endogenous antioxidants, via increased consumption and reduced synthesis. Hyperinsulinaemia enforces glucose fuelling, consuming 4 NAD+ to produce 2 acetyl moieties; beta-oxidation, ketolysis and acetoacetate consume 2, 1 and 0, respectively. This decreases sirtuin, PARPs and oxidative management capacity, leaving reactive oxygen species to diffuse to the cytosol, upregulating aerobic glycolysis, NF-kB and cell division signalling. Also, oxidising cardiolipin, reducing oxidative phosphorylation (OXPHOS) and apoptosis ability; driving a tumourigenic phenotype. Over time, increasing senescent/pathological cell populations occurs, increasing morbidity and mortality. Beta-hydroxybutyrate, an antioxidant, metabolite and signalling molecule, increases synthesis of antioxidants via preserving NAD+ availability and enhancing OXPHOS capacity. Fasting and ketogenic diets increase ketogenesis concurrently decreasing insulin secretion and demand; hyperinsulinaemia inhibits ketogenesis. Lifestyles that maintain lower insulin levels decrease antioxidant catabolism, additionally increasing their synthesis, improving oxidative stress management and mitochondrial function and, subsequently, producing healthier cells. This supports tissue and organ health, leading to a better healthspan, the first challenge that must be overcome in the pursuit of youthful longevity.

3.
Front Endocrinol (Lausanne) ; 14: 1326768, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38189051

RESUMO

Introduction: There is a large heterogeneity in LDL-cholesterol change among individuals adopting ketogenic diets. Interestingly, lean metabolically healthy individuals seem to be particularly susceptible, with an inverse association between body mass index and LDL-cholesterol change. The lipid energy model proposes that, in lean healthy individuals, carbohydrate restriction upregulates systemic lipid trafficking to meet energy demands. To test if anthropometric and energy metabolism markers predict LDL-cholesterol change during carbohydrate restriction. Methods: Ten lean, healthy, premenopausal women who habitually consumed a ketogenic diet for ≥6 months were engaged in a three-phase crossover study consisting of continued nutritional ketosis, suppression of ketosis with carbohydrate reintroduction, and return to nutritional ketosis. Each phase lasted 21 days. The predictive performance of all available relevant variables was evaluated with the linear mixed-effects models. Results: All body composition metrics, free T3 and total T4, were significantly associated with LDL-cholesterol change. In an interaction model with BMI and free T3, both markers were significant independent and interacting predictors of LDL-cholesterol change. Neither saturated fat, HOMA-IR, leptin, adiponectin, TSH, nor rT3 was associated with LDL-cholesterol changes. Discussion: Among lean, healthy women undergoing carbohydrate restriction, body composition and energy metabolism markers are major drivers of LDL-cholesterol change, not saturated fat, consistent with the lipid energy model.


Assuntos
Dieta Cetogênica , Cetose , Humanos , Feminino , Estudos Cross-Over , Glândula Tireoide , Composição Corporal , LDL-Colesterol , Carboidratos
4.
Biomedicines ; 9(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34572351

RESUMO

Patients with type 2 diabetes mellitus (T2DM) and/or cardiovascular disease (CVD), conditions of hyperinsulinaemia, have lower levels of osteocalcin and bone remodelling, and increased rates of fragility fractures. Unlike osteoporosis with lower bone mineral density (BMD), T2DM bone fragility "hyperinsulinaemia-osteofragilitas" phenotype presents with normal to increased BMD. Hyperinsulinaemia and insulin resistance positively associate with increased BMD and fragility fractures. Hyperinsulinaemia enforces glucose fuelling, which decreases NAD+-dependent antioxidant activity. This increases reactive oxygen species and mitochondrial fission, and decreases oxidative phosphorylation high-energy production capacity, required for osteoblasto/cytogenesis. Osteocytes directly mineralise and resorb bone, and inhibit mineralisation of their lacunocanalicular space via pyrophosphate. Hyperinsulinaemia decreases vitamin D availability via adipocyte sequestration, reducing dendrite connectivity, and compromising osteocyte viability. Decreased bone remodelling and micropetrosis ensues. Trapped/entombed magnesium within micropetrosis fossilisation spaces propagates magnesium deficiency (MgD), potentiating hyperinsulinaemia and decreases vitamin D transport. Vitamin D deficiency reduces osteocalcin synthesis and favours osteocyte apoptosis. Carbohydrate restriction/fasting/ketosis increases beta-oxidation, ketolysis, NAD+-dependent antioxidant activity, osteocyte viability and osteocalcin, and decreases excess insulin exposure. Osteocalcin is required for hydroxyapatite alignment, conferring bone structural integrity, decreasing fracture risk and improving metabolic/endocrine homeodynamics. Patients presenting with fracture and normal BMD should be investigated for T2DM and hyperinsulinaemia.

5.
Biomedicines ; 9(7)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34356863

RESUMO

Unlike bolus insulin secretion mechanisms, basal insulin secretion is poorly understood. It is essential to elucidate these mechanisms in non-hyperinsulinaemia healthy persons. This establishes a baseline for investigation into pathologies where these processes are dysregulated, such as in type 2 diabetes (T2DM), cardiovascular disease (CVD), certain cancers and dementias. Chronic hyperinsulinaemia enforces glucose fueling, depleting the NAD+ dependent antioxidant activity that increases mitochondrial reactive oxygen species (mtROS). Consequently, beta-cell mitochondria increase uncoupling protein expression, which decreases the mitochondrial ATP surge generation capacity, impairing bolus mediated insulin exocytosis. Excessive ROS increases the Drp1:Mfn2 ratio, increasing mitochondrial fission, which increases mtROS; endoplasmic reticulum-stress and impaired calcium homeostasis ensues. Healthy individuals in habitual ketosis have significantly lower glucagon and insulin levels than T2DM individuals. As beta-hydroxybutyrate rises, hepatic gluconeogenesis and glycogenolysis supply extra-hepatic glucose needs, and osteocalcin synthesis/release increases. We propose insulin's primary role is regulating beta-hydroxybutyrate synthesis, while the role of bone regulates glucose uptake sensitivity via osteocalcin. Osteocalcin regulates the alpha-cell glucagon secretory profile via glucagon-like peptide-1 and serotonin, and beta-hydroxybutyrate synthesis via regulating basal insulin levels. Establishing metabolic phenotypes aids in resolving basal insulin secretion regulation, enabling elucidation of the pathological changes that occur and progress into chronic diseases associated with ageing.

6.
Open Heart ; 7(2)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32938758

RESUMO

Risk factors for COVID-19 patients with poorer outcomes include pre-existing conditions: obesity, type 2 diabetes mellitus, cardiovascular disease (CVD), heart failure, hypertension, low oxygen saturation capacity, cancer, elevated: ferritin, C reactive protein (CRP) and D-dimer. A common denominator, hyperinsulinaemia, provides a plausible mechanism of action, underlying CVD, hypertension and strokes, all conditions typified with thrombi. The underlying science provides a theoretical management algorithm for the frontline practitioners.Vitamin D activation requires magnesium. Hyperinsulinaemia promotes: magnesium depletion via increased renal excretion, reduced intracellular levels, lowers vitamin D status via sequestration into adipocytes and hydroxylation activation inhibition. Hyperinsulinaemia mediates thrombi development via: fibrinolysis inhibition, anticoagulation production dysregulation, increasing reactive oxygen species, decreased antioxidant capacity via nicotinamide adenine dinucleotide depletion, haem oxidation and catabolism, producing carbon monoxide, increasing deep vein thrombosis risk and pulmonary emboli. Increased haem-synthesis demand upregulates carbon dioxide production, decreasing oxygen saturation capacity. Hyperinsulinaemia decreases cholesterol sulfurylation to cholesterol sulfate, as low vitamin D regulation due to magnesium depletion and/or vitamin D sequestration and/or diminished activation capacity decreases sulfotransferase enzyme SULT2B1b activity, consequently decreasing plasma membrane negative charge between red blood cells, platelets and endothelial cells, thus increasing agglutination and thrombosis.Patients with COVID-19 admitted with hyperglycaemia and/or hyperinsulinaemia should be placed on a restricted refined carbohydrate diet, with limited use of intravenous dextrose solutions. Degree/level of restriction is determined by serial testing of blood glucose, insulin and ketones. Supplemental magnesium, vitamin D and zinc should be administered. By implementing refined carbohydrate restriction, three primary risk factors, hyperinsulinaemia, hyperglycaemia and hypertension, that increase inflammation, coagulation and thrombosis risk are rapidly managed.


Assuntos
Infecções por Coronavirus/terapia , Dieta com Restrição de Carboidratos , Suplementos Nutricionais , Hiperinsulinismo/terapia , Insulina/sangue , Magnésio/uso terapêutico , Pneumonia Viral/terapia , Trombose/terapia , Vitamina D/uso terapêutico , Betacoronavirus/patogenicidade , Biomarcadores/sangue , Glicemia/metabolismo , COVID-19 , Infecções por Coronavirus/sangue , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Suplementos Nutricionais/efeitos adversos , Interações Hospedeiro-Patógeno , Humanos , Hiperinsulinismo/sangue , Hiperinsulinismo/epidemiologia , Cetonas/sangue , Magnésio/sangue , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Prognóstico , Fatores de Risco , SARS-CoV-2 , Trombose/sangue , Trombose/epidemiologia , Trombose/virologia , Vitamina D/sangue , Zinco/uso terapêutico
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