Research on the Efficacy and Safety of Targeted Suprachiasmatic Nucleus Electrical Stimulation for Improving Metabolic Disorders in Patients With Stable Bipolar Disorder Comorbid With Obesity

People with bipolar disorder (BD) have unusually high rates of obesity and metabolic problems, and one leading hypothesis is that a disrupted internal body clock — governed by a brain region called the suprachiasmatic nucleus (SCN) — drives both conditions simultaneously. This trial from the First Affiliated Hospital of Zhejiang University is testing whether a non-invasive brain stimulation technique called temporal interference stimulation (TIS) can reach the SCN deep inside the brain and restore more normal circadian rhythms. TIS works by delivering two slightly offset high-frequency electrical currents through the scalp; where the currents intersect, a low-frequency 'beat' emerges that can stimulate neurons at depth without strongly activating intervening tissue. The study focuses on patients with BD who are currently stable (not in a manic or depressive episode) and who also have obesity, a combination that is both common and therapeutically under-served. The primary biological readout is the circadian rhythm of GLP-1, a hormone that regulates appetite and glucose metabolism, alongside other key metabolic molecules. If TIS can re-entrain SCN-driven rhythms, the hypothesis is that downstream hormonal cycles — including GLP-1 — will normalize, improving metabolic health without the side-effect burden of pharmacotherapy. The trial is currently recruiting, so no outcome data are yet available; this entry documents the rationale and design for future evidence synthesis.

• No outcome data available — trial registered May 2026 and currently recruiting; all findings below are design-level.
• Primary mechanistic target: GLP-1 circadian rhythm amplitude and phase, chosen as a downstream reporter of SCN output with direct relevance to obesity and glucose metabolism.
• Intervention: temporal interference stimulation (TIS) directed at the suprachiasmatic nucleus — a non-invasive deep-brain neuromodulation approach not previously tested in this BD-plus-obesity population (best-effort inference from title and abstract; low confidence on full protocol details).

This is a registered interventional trial (NCT07589647) conducted at the First Affiliated Hospital of Zhejiang University, recruiting as of May 2026. Eligible participants are adults with a confirmed diagnosis of bipolar disorder in the stable phase who also meet criteria for obesity. The intervention is temporal interference stimulation (TIS) targeted at the suprachiasmatic nucleus; full details of session frequency, stimulation parameters, sham-control design, and follow-up duration are not specified in the available abstract and should be confirmed in the full protocol registration. Outcome measures include circadian profiles of GLP-1 and other metabolic molecules, with the stated goal of elucidating molecular mechanisms of metabolic dysregulation in this comorbid population. Note: sample size, randomisation details, and blinding procedures are not described in the source abstract — confidence in methods summary is low.

Because the trial is still recruiting, no efficacy or safety data exist and no conclusions can yet be drawn about whether TIS improves metabolic outcomes in this population. The abstract does not specify sample size, which makes it impossible to assess statistical power to detect clinically meaningful changes in GLP-1 rhythm or body composition metrics. It is unclear whether a sham-stimulation control arm is included, which is critical for disentangling specific TIS effects from expectation or non-specific arousal effects. The next essential experiment would be a fully reported, adequately powered RCT with blinded GLP-1 sampling at multiple circadian time points and pre-registered metabolic endpoints.

This trial sits at the intersection of circadian neuroscience and metabolic medicine, extending the mechanistic framework elaborated in [§44] (CLOCK-BMAL1 circadian machinery as a therapeutic target) by moving from molecular biology to direct neuromodulation of the master circadian pacemaker in human subjects. It parallels [§133], which examines circadian disruption, light, and central oxidative stress, in that both articles implicate SCN-level circadian dysfunction as upstream of downstream physiological pathology; however, this trial proposes electrical correction of SCN output rather than light-based entrainment. The focus on a GLP-1 circadian readout as a proxy for SCN-metabolic coupling indirectly connects to [§108], which demonstrates that chronic jet-lag (a model of SCN disruption) worsens diet-induced metabolic and renal injury in mice, providing pre-clinical plausibility for the trial's core hypothesis. The study also parallels [§33] (time-restricted eating for Alzheimer's disease), in that both interventions attempt to re-synchronise circadian-metabolic axes through non-pharmacological means in neuropsychiatric populations, though the mechanistic entry points — neural stimulation versus feeding schedule — differ substantially.

• The CLOCK-BMAL1 complex in circadian regulation: structure, mechanisms, and therapeutic targeting
  Provides the molecular circadian clock framework (CLOCK-BMAL1) that mechanistically underpins why SCN stimulation might normalise metabolic rhythms; essential context for interpreting TIS target selection.
• Sleep, Light, Circadian, Central Oxidative Stress
  Also implicates SCN-level circadian disruption in systemic pathology but investigates light and oxidative stress rather than electrical stimulation, allowing readers to compare entrainment modalities.
• Effects of chronic jetlag on high-fat and high-fructose diet induced renal injury in mice
  Pre-clinical evidence that chronic SCN rhythm disruption (jet-lag model) directly worsens metabolic injury, offering animal-model plausibility for the trial's central mechanistic claim.
• TREAD: Time Restricted Eating Intervention for Alzheimer's Disease
  A parallel non-pharmacological circadian-metabolic intervention trial (time-restricted eating in a neuropsychiatric population) against which design choices, feasibility, and outcome selection can be benchmarked.
• Enhancing Slow Wave Sleep in Depression
  Tests a different neuromodulatory approach (slow-wave sleep enhancement) for a mood disorder with metabolic implications, providing a comparator for non-invasive brain stimulation strategies in psychiatric populations.