Semaglutide in sepsis, schizophrenia, and heart failure adds detail

A 2026 study in rats and heart cells found that semaglutide reduced a specific type of cell death after injury and infection ¹. The researchers used rats that had both a crushed limb and a procedure called cecal ligation and puncture, which creates an infection in the abdomen. This combination led to heart problems that can follow serious injury and infection, called post-traumatic septic myocardial dysfunction (PT-SIMD) ¹. The researchers then used a protein-mapping method called quantitative 4D-DIA proteomic profiling on heart tissue ¹.

The injured hearts had markers of ferroptosis, a form of cell death driven by iron and damage to fats. They had more ACSL4, a protein that promotes this cell death, and less of two protective proteins, GPX4 and FSP1. They also had 4-HNE, a marker of fat damage ¹.

The protein map also found lower levels of March5, a protein in mitochondria, the energy-producing parts of cells. March5 is an E3 ubiquitin ligase, meaning it tags other proteins for removal ¹. In heart cells from newborn rats, a bacterial toxin called lipopolysaccharide reduced March5 in a way that depended on dose and time ¹.

When the researchers lowered March5 using small interfering RNA, a gene-silencing tool, ferroptosis got worse, with more ACSL4, more free iron, and more fat damage. Treating the cells with semaglutide raised March5, reduced ACSL4, and reduced the cell death. But when March5 was removed, semaglutide no longer protected the cells ¹.

This suggests a specific sequence: March5 normally suppresses ferroptosis by keeping ACSL4 in check, and semaglutide seems to work through that March5-ACSL4 path ¹. The study was done in rats and isolated heart cells, so it does not show the same effect in people ¹. It adds mechanistic detail beyond the cardiovascular outcomes seen in large diabetes and obesity trials ⁴.

Interviews with 11 people with schizophrenia found that semaglutide reduced antipsychotic-related hunger pain, but some people also had negative experiences from reduced hunger ². This was a qualitative study from a trial called HISTORI. The researchers interviewed people who had finished semaglutide treatment for prediabetes linked to antipsychotic medicines ². The interviews took place four months to one and a half years after treatment ended ².

The reflexive thematic analysis, a method for finding patterns in interviews, found three themes: "Hunger pain induced by antipsychotic medicine," "Positive and negative experiences of reduced hunger," and "Eating habits and what influences them" ².

People described hunger pain as an excruciating combination of constant hunger, never feeling full, and constant thoughts about food. This pain, probably caused by antipsychotics, seemed to reinforce unhealthy coping styles ². Semaglutide reduced that hunger pain, and most participants felt freed by the relief. The study also found that reduced hunger had negative effects for some people, and the authors recommend checking patients' eating problems before treatment ².

This matches the known way semaglutide works in the brain. It activates GLP-1 receptors, proteins that respond to a gut hormone, on appetite-regulating nerve cells in the hypothalamus, a brain region that controls hunger. This increases feelings of fullness ⁵. The interviews add a patient-reported view beyond the weight loss and blood sugar control shown in large clinical trials and real-world studies ⁶.

A 2026 systematic review found that semaglutide improves symptoms and exercise ability in people with obesity-related heart failure, but a different drug class still has the most outcome data ³. The review followed structured reporting guidelines called PRISMA and looked at drug therapy for obesity-driven heart failure with preserved ejection fraction (HFpEF), a type of heart failure where the heart pumps normally but has trouble filling ³. The authors searched several databases through December 2025 and included 18 reports ³.

They concluded that a drug class called sodium-glucose cotransporter 2 inhibitors, which help the kidneys remove sugar, has the most complete outcome data. So these drugs form the foundation of treatment ³.

For semaglutide, the review found that trials in obesity-related HFpEF show improvements in symptoms, physical limits, exercise capacity, and body weight ³. Tirzepatide, a dual GIP/GLP-1 receptor agonist, meaning it acts on two gut-hormone receptors, went further by improving clinical status and reducing worsening heart failure events ³. The review describes obesity-driven HFpEF as a metabolic syndrome that shows up as heart failure. Treatment follows a sequence based on the person's presentation: diagnosis, fluid removal, SGLT2 inhibition, obesity-directed therapy, and selective add-on treatment ³.

This review places semaglutide within a wider treatment plan. It is consistent with existing cardiovascular evidence: in a large combined analysis of trials, semaglutide reduced major adverse cardiovascular events, a combined measure of serious heart and blood vessel problems, by about 29% compared with placebo or other treatments ⁴. The HFpEF data add a specific heart failure type where symptom burden and exercise capacity matter, not just event rates ³.

The three studies provide different kinds of evidence. The rat and cell study identifies a new target, March5, but does not test outcomes in people ¹. The interview study has a small sample and captures patient experience rather than how well the drug works ². The systematic review combines randomized trial data and offers a practical treatment framework ³.

Below is a simple comparison:

Study	What it did	Main finding
Rat and cell study 1	Used a rat model of injury plus infection and heart cells	Semaglutide reduced a type of iron-driven cell death through the March5-ACSL4 path
Interview study 2	Interviewed 11 people with schizophrenia after semaglutide	Semaglutide reduced antipsychotic hunger pain, but reduced hunger also had downsides
Systematic review 3	Reviewed 18 reports on drugs for obesity-related heart failure	Semaglutide improved symptoms and exercise, but SGLT2 inhibitors had the most outcome data

None of the new studies changes the core findings for semaglutide: it lowers HbA1c, a measure of long-term blood sugar, reduces body weight, and protects against major adverse cardiovascular events and kidney disease progression ⁴. The new work adds mechanistic detail, patient-reported nuance, and placement within obesity-related heart failure ¹.

A recurring theme is that semaglutide's effects go beyond blood sugar control. The sepsis study points to ferroptosis suppression through March5, a path not previously documented for semaglutide ¹. The interview study shows that appetite suppression can feel like relief from antipsychotic-induced hunger pain, but can also be a downside when hunger is already low ². The heart failure review places semaglutide as an obesity-directed therapy after SGLT2 inhibition, not as a primary hormonal treatment for heart failure ³.

The safety picture from these sources stays consistent with existing evidence. The interview study did not report new safety concerns, but it stressed checking eating problems before treatment ². The heart failure review did not raise unexpected safety concerns for semaglutide in this population ³. The sepsis study was done in rats and cells, so it did not provide human safety data ¹. Gastrointestinal side effects remain the most common documented issue in clinical use ¹⁰.

Several questions remain open. The March5-ACSL4 ferroptosis path has not been confirmed in human sepsis-related heart dysfunction, and no clinical trial has tested semaglutide for that condition ¹. The findings from 11 interviews cannot show how common these experiences are or prove cause and effect, and it is unknown whether the hunger relief leads to lasting behavior change ². The heart failure review reports symptom and exercise improvements, but longer-term data on heart failure hospitalizations and cardiovascular death for semaglutide in obesity-driven HFpEF are still limited. The strongest outcome data were for SGLT2 inhibitors, not for GLP-1 receptor agonists, meaning drugs that activate the GLP-1 receptor, the class semaglutide belongs to ³.

It is also unclear how semaglutide interacts with antipsychotic-induced hunger after treatment ends. The authors found that reduced hunger had negative effects for some participants, but the study did not measure long-term nutrition or weight maintenance ². It remains unknown whether specific antipsychotics change semaglutide's appetite effects in the brain.

Finally, the sepsis and heart failure findings come from different biological areas. The ferroptosis mechanism in rats does not automatically apply to heart failure with preserved ejection fraction in humans, even though both involve heart function. The evidence still cannot say whether semaglutide's heart-protective effects share a common path across these conditions or work through separate mechanisms ¹.