Leptin (116-130), amide, mouse: Mechanism, Evidence, Protocols

Executive Summary: Leptin (116-130), amide, mouse is a synthetic peptide fragment of the native adipocyte-derived hormone, with the sequence Ser-Cys-Ser-Leu-Pro-Gln-Thr-Ser-Gly-Leu-Gln-Lys-Pro-Glu-Ser-NH2, and is highly soluble in DMSO and water under laboratory conditions (APExBIO product page). It models the metabolic and pleiotropic effects of full-length leptin, enabling high-specificity research in energy homeostasis, obesity, and leptin deficiency (see related article). The peptide's bioactivity includes modulation of food intake, body weight, and peripheral immune responses. Its application extends to robust, reproducible cell-based and in vivo assays, provided protocols adhere to strict storage and solubility recommendations. This review integrates structural properties, current evidence, and optimized workflow guidance for advanced metabolic and immunological research.

Biological Rationale

Leptin is a 16-kDa cytokine-like hormone produced predominantly by adipocytes and acts as a central regulator of energy balance and food intake. The Leptin (116-130), amide, mouse fragment corresponds to a 15-amino-acid C-terminal region, which retains biological activity relevant to energy homeostasis regulation and peripheral immunomodulatory functions (APExBIO). This fragment is valuable in research models of obesity, diabetes, and infertility related to leptin signaling defects. By selectively mimicking the actions of native leptin, it allows for the dissection of leptin-dependent pathways without full-length protein confounders (see advanced assay guidance). The sequence's high solubility in water (≥24.15 mg/mL) and DMSO (≥156 mg/mL) further enables precise dosing in experimental protocols, as detailed by the manufacturer.

Mechanism of Action of Leptin (116-130), amide, mouse

The Leptin (116-130), amide, mouse peptide binds to leptin receptors (Ob-R), triggering downstream JAK-STAT and PI3K signaling pathways that modulate appetite, energy expenditure, and metabolic rate. Although truncated, this fragment retains the receptor-interacting domain necessary for activity in murine models (mechanistic details). Central nervous system effects include suppression of orexigenic neuropeptides and stimulation of anorexigenic signals. In peripheral tissues, leptin fragments influence hematopoiesis, angiogenesis, bone mass, and immune cell homeostasis. The pleiotropic effects of leptin, including modulation of T lymphocyte function, underscore its expanding role in immunometabolism and inflammatory response regulation (APExBIO).

Evidence & Benchmarks

• Leptin (116-130), amide, mouse induces dose-dependent reductions in food intake and body weight in leptin-deficient (ob/ob) rodents, paralleling full-length leptin effects (APExBIO).
• This fragment demonstrates high aqueous solubility (≥24.15 mg/mL) and DMSO compatibility (≥156 mg/mL), enabling precise, reproducible dosing for in vitro and in vivo studies (product info).
• In metabolic research, Leptin (116-130), amide, mouse is validated as a benchmark peptide for modeling leptin resistance and energy homeostasis mechanisms (assay guidance).
• Peripheral effects extend to modulation of hematopoiesis, angiogenesis, and immune cell activity, as shown in controlled murine studies (APExBIO).
• Solutions should be prepared fresh and used promptly; long-term storage in solution leads to loss of activity, as reported in comparative workflow analyses (protocol troubleshooting).

Applications, Limits & Misconceptions

Leptin (116-130), amide, mouse is used in obesity and diabetes research to evaluate energy homeostasis and leptin signaling pathway integrity. Its solubility and stability profile make it suitable for high-throughput screening and cell-based assays (assay protocols). The fragment is also employed in studies of immune-metabolic crosstalk and leptin-deficiency-related infertility. However, the use of this peptide in cardiovascular or inflammasome-targeted studies should be limited to validated protocols, as direct evidence for such cross-domain effects remains insufficient in the peer-reviewed literature. APExBIO supplies this product for research use only; it is not intended for diagnostic or clinical applications.

Common Pitfalls or Misconceptions

• The peptide does not fully recapitulate all endocrine effects of native leptin; use is limited to pathways involving the 116-130 region.
• Long-term storage of prepared solutions leads to peptide degradation and loss of bioactivity; always prepare fresh aliquots (APExBIO).
• Insoluble in ethanol; attempting to dissolve in non-recommended solvents will result in precipitation and assay failure.
• Not validated for human diagnostic, therapeutic, or clinical use—research applications only.
• Cross-domain effects (e.g., direct cardiovascular modulation) are not supported by primary research for this fragment.

Workflow Integration & Parameters

For optimal use in metabolic and immunological workflows, Leptin (116-130), amide, mouse should be handled as follows:

Protocol Parameters

• Solubility: Dissolve in DMSO at ≥156 mg/mL or water at ≥24.15 mg/mL at room temperature; vortex gently to ensure homogeneity.
• Storage: Store lyophilized peptide desiccated at -20°C; avoid repeated freeze-thaw cycles.
• Solution Preparation: Prepare fresh solutions immediately before use; do not store in solution for more than 24 hours at 4°C.
• Application: For in vivo studies, deliver via intraperitoneal or subcutaneous injection in validated buffers; for cell-based assays, dilute in serum-free media to the desired working concentration.
• Assay Controls: Always include vehicle and full-length leptin controls for benchmarking fragment activity.

This article extends previous protocol discussions by integrating controlled peptide stability studies and comparative solubility data (see protocol-driven guide).

Conclusion & Outlook

Leptin (116-130), amide, mouse, as supplied by APExBIO, is a validated, highly soluble peptide fragment for dissecting leptin signaling and energy homeostasis regulation in obesity and diabetes research. Its robust performance in preclinical models is underpinned by precise solubility, storage, and application parameters. While its use in immunometabolic research is expanding, direct translation to other domains such as cardiovascular inflammation requires additional primary evidence. Researchers are advised to follow protocol recommendations for maximum reproducibility and data integrity.