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- Ketogenic diet, by replacing glucose with ketones as an energy source, lessens alcohol cravings among people with alcohol use disorders.
- Omega-3 fatty acids reduce the risk of cardiovascular disease-related death by up to 23 percent, especially in people with high triglyceride levels.
- Women see a 24 percent drop in premature death risk with just 140 minutes of weekly activity – half the time men need for similar benefits.
- Aging undermines the brain's capacity for maintaining working memory, with subtle declines in neuron activity and connectivity in the prefrontal cortex.
Berberine has shown promise for improving blood sugar and cholesterol levels, but whether these effects translate into a lower risk of disease remains unclear. To explore this question, researchers examined how biological changes associated with berberine relate to ischemic heart disease and diabetes.
The study randomly assigned 84 Chinese men with elevated blood lipids to 500 mg of berberine twice daily or placebo for 12 weeks. Using blood samples from 80 participants, they identified a pattern of 18 proteins, testosterone, and sex hormone-binding globulin (SHBG) associated with berberine treatment. They then looked for this pattern in 14,721 men from the UK Biobank to examine its links to diabetes and ischemic heart disease (a condition in which the heart muscle receives too little blood). Blood lipid analyses used a subset of 3,750 men.
- The berberine-related blood pattern was associated with 13% lower odds of ischemic heart disease and 34% lower odds of diabetes.
- The blood pattern was linked to lower cholesterol in certain LDL and VLDL subtypes, and lower triglycerides in subtypes of LDL, VLDL, HDL, and IDL.
- Higher levels of SHBG were associated with lower odds of both diseases, while higher testosterone was linked to lower diabetes odds.
- Genetic analyses provided additional evidence that some of these associations might be causal, but the results were not consistent across all tests.
Berberine may influence heart disease and diabetes through several biological pathways. Some of the proteins identified in the study help regulate fat metabolism, while others are involved in inflammation, blood clotting, and the release of gut hormones such as GLP-1, which helps regulate blood sugar. Changes in these processes could potentially improve cardiovascular and metabolic health.
The findings highlight how berberine may affect heart disease and diabetes through different biological pathways. Identifying which changes contribute to better health could help clarify its therapeutic potential, although whether berberine prevents either disease remains unknown.
Bone cells can sense physical forces and adapt to the loads placed on them. A new study investigated whether this ability also influences aging and lifespan beyond the skeleton.
Researchers randomly assigned 20-month-old male and female mice to mechanical loading of both shinbones twice weekly for four months or no loading. The study assessed lifespan, memory, physical performance, metabolism, and immune-cell changes. In a separate experiment, the researchers disabled Piezo1, a protein that allows bone cells to sense mechanical forces, to examine its role in aging.
- Bone loading extended median lifespan by 9.4% (about 80 days) and improved memory, coordination, strength, and blood sugar regulation in old mice.
- Removing Piezo1 from bone cells shortened the median lifespan by 13.2% in males and 10.7% in females.
- Middle-aged mice showed better memory and movement after receiving plasma (the liquid portion of blood) from older mice that underwent bone loading than from older mice that did not.
Bone cells use Piezo1 to sense mechanical forces and regulate the proteins they release into the blood. One of these, PEDF, may protect nerve cells from damage and reduce abnormal fat buildup in the liver. Bone loading increased PEDF levels, while separate PEDF injections improved memory and coordination and reduced cellular senescence (when cells permanently stop dividing). Bone loading also shifted the balance of immune cells in the bone marrow toward T and B cells, which provide targeted immune defenses, and away from myeloid cells, some of which promote inflammation. Together, these changes may help explain the broader benefits.
The findings suggest that bones may play a broader role in healthy aging than previously recognized. Even later in life, their response to mechanical forces could help maintain the function of other organs.
In Aliquot #83, I discuss lifestyle habits that help maintain bone health as we age.
High salt intake has been linked to poorer cognition, but much less is known about how very low salt intake affects the brain. A new study investigated how both extremes of salt intake might affect memory.
Researchers randomly assigned 32 male mice to four groups for 14 weeks. To better reflect the human gut microbiome, three groups received gut microbes from healthy human donors and ate diets containing 0.1%, 0.5%, or 8% salt, with eight mice per group. The fourth group retained its natural gut bacteria and ate 0.5% salt as an additional control. Memory was assessed by testing how well the mice recognized familiar objects and remembered locations over short periods.
- Both very low and very high salt intake impaired the mice's ability to recognize familiar objects and remember locations. The effects were more pronounced with high salt.
- Both salt extremes reduced stool levels of propionate and butyrate, two short-chain fatty acids produced by gut bacteria. Low salt also reduced two other short-chain fatty acids, acetate and isobutyrate, while high salt did not significantly affect either.
- High salt increased four blood inflammatory markers, while low salt showed no clear increases.
- Both extreme salt intakes reduced three proteins that support nerve-cell connections in the hippocampus, a brain region important for memory, including BDNF. A fourth declined significantly only with high salt.
Gut microbes produce short-chain fatty acids that help regulate immune activity and communication between the gut and brain. When levels of these compounds decline, this communication may be disrupted, potentially affecting the nerve-cell connections involved in learning and memory. High salt intake may further interfere with these processes by increasing inflammation, offering a possible explanation for its stronger effects on memory.
The findings suggest that salt’s effects on memory may depend partly on how it changes the gut’s metabolic activity. Preserving the production of beneficial compounds by gut microbes could therefore be an important part of protecting brain function.
