Health
“A 2026 study published in Molecular Psychiatry found that exercise increases apelin levels in muscle and brain, and apelin interacts with APJ receptors on hippocampal neurons, helping explain exercise's antidepressant effects in a rat model." (Accompanying post image headline: "LATIHAN BEBAN 'dapat mengurangi' DEPRESI", i.e. "WEIGHT…”
This post lists 4 claims. We checked item 2.
Plain restatementA 2026 paper in Molecular Psychiatry reported that exercise raised apelin levels in rodents, that apelin acts on APJ receptors on hippocampal neurons, and that this pathway mediates the antidepressant-like effects of exercise in a rodent model. The post presents this as evidence that weight training can reduce depression.
General information only - not medical advice.
The study is real. A 2026 paper in Molecular Psychiatry by Yu and colleagues reported that four weeks of voluntary running raised apelin levels, that muscle is the main source of that apelin, and that apelin acting on APJ receptors in the hippocampus is needed for the antidepressant-like and brain-cell-growth effects of exercise. Two things in the post do not match the paper. The experiments were done in mice, not rats, and the exercise was aerobic wheel running, not weight training, so the post's headline about weight training is not supported by the study it cites. Separately, there is human trial evidence that resistance training can reduce depressive symptoms, but that comes from different research and has nothing to do with apelin. What remains unknown is whether this muscle-to-brain apelin pathway works the same way in people, since the paper contains no human data. The post is right to note that exercise does not replace medical treatment for depression. General information only, not medical advice.
A 2026 [drifted from the evidence:] study published in Molecular Psychiatry [drifted from the evidence:] found that exercise [drifted from the evidence:] increases apelin levels in [drifted from the evidence:] muscle and brain, and apelin [drifted from the evidence:] interacts with APJ receptors on hippocampal neurons, [drifted from the evidence:] helping explain exercise's antidepressant effects in a [drifted from the evidence:] rat model." [drifted from the evidence:] (Accompanying post [drifted from the evidence:] image headline: "LATIHAN BEBAN 'dapat mengurangi' DEPRESI", i.e. "WEIGHT TRAINING 'can reduce' DEPRESSION".)
A 2026 [added by the neutral restatement:] paper in Molecular Psychiatry [added by the neutral restatement:] reported that exercise [added by the neutral restatement:] raised apelin levels in [added by the neutral restatement:] rodents, that apelin [added by the neutral restatement:] acts on APJ receptors on hippocampal neurons, [added by the neutral restatement:] and that this pathway mediates the antidepressant-like effects [added by the neutral restatement:] of exercise in a [added by the neutral restatement:] rodent model. [added by the neutral restatement:] The post [added by the neutral restatement:] presents this as evidence that weight training can reduce depression.
Red-tinted words in the claim drifted from the evidence. Green-tinted words are what a neutral restatement needs.
The trace / claim to source
- A 2026 Molecular Psychiatry study on this exact topic exists, by Yu et al., and the journal and year are correctly stated.
- Exercise increased apelin: specifically serum and hippocampal apelin rose after four weeks of voluntary running, with skeletal muscle identified as the primary source.
- Apelin acting on APJ receptors on hippocampal neurons is the central mechanism reported, and APJ knockdown reduced the antidepressant and pro-neurogenic effects of running.
- The framing as a mechanistic animal finding, not a human clinical result, is broadly consistent with the paper, and the post's body text correctly calls it mechanistic evidence in a rodent model.
- The post's closing disclaimer that exercise does not replace medical treatment for depression is consistent with mainstream clinical guidance.
- Modality mismatch, the main problem: the post's headline attributes the finding to "latihan beban" (weight or resistance training). The study tested voluntary wheel running, an aerobic activity. The paper provides no evidence about resistance training. Human resistance-training evidence for depression exists separately but is unrelated to this paper and to apelin.
- Species error: the claim says "rat model". The experiments were in mice. This does not change the human-relevance caveat, but it is factually incorrect as stated in the English claim.
- Minor imprecision: the claim says apelin increased "in muscle and brain". The reported increases were in serum and hippocampus, with muscle identified as the source tissue rather than the site of measured increase.
- Species extrapolation risk: although the post does flag the rodent model, placing a human-facing headline about reducing depression above a mouse-only mechanistic study invites readers to treat preclinical findings as a demonstrated human outcome.
- Effect sizes, confidence intervals, group sizes, and the authors' own stated limitations were not retrieved, because only abstract-level and secondary-source detail was accessible.
- Whether the published version differs from the online-ahead-of-print record could not be checked.
- Whether apelin plays the same role in humans is untested in this paper and remains an open question.
- Whether the post author intended "model tikus" as mouse or rat cannot be determined from the post alone.
The study exists and is correctly identified by journal and year. It is by Jiasui Yu and colleagues, published in Molecular Psychiatry in 2026, online ahead of print, doi 10.1038/s41380-026-03651-y. The authors evaluated apelin as a mediator of the antidepressant effects of physical exercise, testing whether exercise-induced increases in skeletal muscle-derived apelin enhance hippocampal plasticity via apelin and its APJ receptor. Voluntary running for 4 weeks alleviated depression-like behaviors and increased serum and hippocampal apelin levels, with the tibialis anterior and gastrocnemius muscles as the primary apelin sources; muscle-specific apelin knockout abolished the antidepressant and pro-neurogenic effects of running, while muscle-targeted apelin overexpression mimicked the benefits of running in wild-type mice. Mechanistically, apelin enhanced NMDA receptor-mediated neurotransmission via APJ receptors on hippocampal glutamatergic neurons, and knockdown of APJ diminished the pro-neurogenic and antidepressant effects of running. Apelin/APJ signaling was reported to activate casein kinase 2, which phosphorylated the GluN2B subunit at serine 1480, enhancing NMDA receptor function and activating downstream calpain-2 signaling. The species is mice, not rats. The experiments used male mice: six-week-old animals were exposed to mild unpredictable stress for four weeks to induce depression-like behaviors, and some were then given access to a running wheel for voluntary exercise for another four weeks. Mice bred to lack muscle apelin showed no improvement in depression-like behavior after running and no increase in adult neurogenesis. On the post's headline framing about weight training, separate human evidence does exist but comes from a different body of work. A meta-analysis of randomized clinical trials found that resistance exercise training significantly reduced depressive symptoms among adults regardless of health status or total prescribed volume, published in JAMA Psychiatry in 2018 and drawing 54 effects from 33 randomized clinical trials. That study is unrelated to apelin and was not part of the 2026 Molecular Psychiatry paper.
Complete reasoning
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Is the study about weight training reducing depression real?
A 2026 study in Molecular Psychiatry by Yu and colleagues does exist and looked at exercise, apelin, and depression-like behavior. But it tested voluntary wheel running, which is aerobic exercise, not weight training, so the headline's claim about weight training is not supported by this study.
Did the study use rats or mice?
The study used mice, not rats. The post's claim of a 'rat model' is factually incorrect.
What did the study actually find?
Four weeks of voluntary running raised apelin levels in the blood and hippocampus of mice, with skeletal muscle as the main source. Apelin acting on APJ receptors on hippocampal neurons was needed for the antidepressant-like and brain-cell-growth effects of running.
Is there any real evidence that weight training helps with depression?
Yes, but it comes from a separate line of research. A 2018 JAMA Psychiatry meta-analysis of human clinical trials found that resistance training reduced depressive symptoms in adults. That finding is unrelated to the apelin study and does not involve apelin at all.
Does this mean the apelin pathway works the same way in humans?
The investigation did not establish this. The 2026 paper contains no human data, so whether the muscle-to-brain apelin pathway functions the same way in people remains unknown.