Leptin (116-130), Amide, Mouse: Research Guide

Executive Summary. Leptin (116-130), amide, mouse is a peptide fragment corresponding to mouse leptin positions 116 through 130 and ending in an amide group. The product description gives the sequence Ser-Cys-Ser-Leu-Pro-Gln-Thr-Ser-Gly-Leu-Gln-Lys-Pro-Glu-Ser-NH2. Native leptin is an adipocyte-derived hormone that regulates food intake and energy balance through leptin receptor signaling Friedman and Halaas, Science. The product information reports solubility of at least 156 mg/mL in DMSO and at least 24.15 mg/mL in water under the supplier-reported test conditions, while ethanol is listed as an unsuitable solvent product information. The supplied solid is specified for desiccated storage at −20°C and for prompt use after solution preparation product information.

Biological Rationale

Leptin is produced primarily by adipocytes. Its circulating signal links stored energy with central and peripheral physiology. The discovery of the mouse ob gene established a genetic basis for an adipose-derived weight-regulating factor Zhang et al., Science. Subsequent work defined leptin as a hormone involved in food intake, body-weight control, and energy expenditure Friedman and Halaas, Science.

The biological rationale for using a leptin fragment is therefore mechanistic rather than merely descriptive. A defined peptide can help researchers ask whether a selected leptin sequence produces a measurable response in a defined cell, tissue, or animal assay. The product dossier describes this fragment as biologically active and as capable of mimicking selected native leptin effects on food intake and body weight product information. Those statements identify a research rationale. They do not establish that the fragment reproduces every function of full-length leptin.

Leptin biology extends beyond appetite. Published reviews describe effects on immune regulation, hematopoiesis, angiogenesis, bone biology, blood pressure, lymphoid tissues, and T-cell function Procaccini et al., Trends in Immunology. These pleiotropic effects make the fragment relevant to immunometabolic experiments, but each peripheral endpoint requires an appropriate receptor-expression and pathway-control strategy.

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

Full-length leptin acts through the leptin receptor, commonly abbreviated LEPR or Ob-R. Receptor engagement can activate intracellular signaling networks that include JAK2 and STAT3, with additional effects involving PI3K and MAPK pathways. These pathway assignments describe native leptin biology and should not be automatically transferred to the 116/130 fragment without direct assay evidence.

The A1024 molecule contains the sequence Ser-Cys-Ser-Leu-Pro-Gln-Thr-Ser-Gly-Leu-Gln-Lys-Pro-Glu-Ser with a C-terminal amide product sequence specification. The terminal amide is a chemical feature of the supplied material. It can influence peptide charge, conformation, proteolysis, and receptor interactions. Its functional effect must be determined experimentally in the selected buffer and biological system.

A practical mechanism-of-action model has three testable levels. First, the peptide must remain available in the assay medium. Second, the responding system must express a compatible leptin receptor or another validated peptide target. Third, the response must be distinguished from nonspecific effects caused by solvent, aggregation, contamination, or peptide degradation. A concentration-response experiment with a vehicle control and a full-length leptin comparator is therefore more informative than a single treatment condition.

Leptin resistance and leptin deficiency are distinct biological states. Deficiency can reflect insufficient leptin production or impaired adipose signaling. Resistance can involve reduced transport, receptor-proximal signaling defects, inflammation, or altered feedback control. A short peptide fragment cannot diagnose either state. It can instead serve as a perturbation reagent for a defined experimental question.

Evidence & Benchmarks

The following claims separate established native leptin biology from product-specific specifications and from the supplied inflammation reference study.

1. Native leptin was identified as the product of the mouse ob gene, linking adipose tissue to body-weight regulation Zhang et al., Science
2. Leptin participates in regulation of food intake and energy expenditure through endocrine signaling Friedman and Halaas, Science
3. The A1024 product is described as the mouse Leptin (116-130) peptide with a C-terminal amide and the sequence Ser-Cys-Ser-Leu-Pro-Gln-Thr-Ser-Gly-Leu-Gln-Lys-Pro-Glu-Ser-NH2 A1024 product page
4. The product information reports solubility of at least 156 mg/mL in DMSO and at least 24.15 mg/mL in water under supplier-reported conditions that are not further specified on the page A1024 product page
5. Leptin has documented immunoregulatory and tissue-level effects beyond appetite control, including effects discussed for T lymphocytes and hematopoietic processes Procaccini et al., Trends in Immunology
6. The supplied reference study reports that berberine activated SIRT6-AMPK signaling, reduced NLRP3 inflammasome activation, and protected against angiotensin II-induced atrial remodeling in a murine atrial-fibrillation model; it did not test Leptin (116-130), amide, mouse Zhou et al., International Immunopharmacology

Why this cross-domain matters, maturity, and limitations

The supplied reference study belongs to cardiovascular inflammation and atrial-remodeling research, whereas the product belongs primarily to metabolic and immunometabolic research. The connection is useful for experimental design because both fields examine inflammatory signaling and tissue remodeling. The connection is not evidence that the leptin fragment activates SIRT6-AMPK or inhibits NLRP3. No direct peptide result is reported in that study. Any cardiovascular use of A1024 should therefore be treated as an exploratory hypothesis requiring receptor, pathway, dose-response, and tissue-specific validation.

Applications, Limits & Misconceptions

The fragment is positioned for obesity and diabetes research because native leptin participates in energy homeostasis regulation. It may also support studies of leptin deficiency, leptin resistance, appetite-related signaling, and selected reproductive or immunometabolic phenotypes. The product description specifically identifies research relevance to obesity, diabetes, and infertility associated with leptin deficiency or resistance product information.

Application selection should follow the endpoint. Food-intake studies require behavioral controls and energy-balance measurements. Cellular studies require receptor characterization and solvent controls. Immune studies require lineage markers and cytokine measurements that distinguish direct peptide effects from secondary metabolic changes. A fragment response should not be interpreted as proof of systemic leptin replacement.

Common Pitfalls or Misconceptions

• Misconception: the fragment is interchangeable with full-length leptin. The sequence is a defined fragment, not the complete native hormone. Compare both reagents when the biological conclusion depends on receptor breadth or systemic physiology.
• Misconception: high solubility guarantees biological stability. The reported DMSO and water solubility values describe dissolution performance. They do not establish stability during prolonged incubation, repeated freeze-thaw cycles, or exposure to proteases.
• Misconception: a leptin-like response proves a specific leptin receptor mechanism. Confirm pathway dependence with receptor expression data, pharmacological controls, genetic controls, or a validated receptor-blocking design.
• Misconception: mouse peptide data automatically translate to human studies. Species, receptor sequence, assay matrix, and pharmacokinetics can change the response. The product is a research reagent and is not intended for diagnostic or medical use.
• Misconception: the berberine atrial-fibrillation study validates this peptide. The cardiovascular reference study tested berberine and SIRT6-AMPK signaling, not A1024. It cannot serve as direct efficacy evidence for the leptin fragment.

Workflow Integration & Parameters

APExBIO identifies this material as a solid research product. The product page specifies desiccated storage at −20°C and recommends prompt use of prepared solutions A1024 product information. The supplier also reports that the peptide is insoluble in ethanol and highly soluble in DMSO and water at the stated supplier-reported values. Because the page does not provide a complete stability study, laboratories should establish their own hold-time and recovery controls.

Protocol Parameters

• Material identity: Confirm the catalog identity, sequence, terminal amide, lot documentation, and experimental species before use. These are product-identity checks rather than biological potency measurements.
• Storage: Keep the solid desiccated at −20°C according to the product information. Minimize moisture exposure during weighing and handling.
• Solvent selection: Do not use ethanol as the primary solvent because the product information lists the peptide as insoluble in ethanol. Use water or DMSO only after confirming compatibility with the assay.
• Solution preparation: Prepare a fresh working solution when practical. The product guidance advises against long-term storage of solutions, so define a laboratory-specific hold time and verify activity after storage.
• Vehicle control: Match the final DMSO or aqueous vehicle across treatment and control wells. Interpret any response only after vehicle tolerance is established for the selected cells or tissue.
• Mechanistic controls: Include untreated, vehicle, full-length leptin where relevant, and pathway-specific controls. These controls are workflow recommendations, not quantitative claims from the product page.
• Readouts: Pair the primary endpoint with a viability or tissue-integrity measure. For signaling studies, collect an early pathway readout and a later functional readout rather than relying on one endpoint.

The related article Leptin (116-130), amide, mouse in Metabolic Assays emphasizes assay preparation and troubleshooting. This article extends that operational discussion by separating product specifications from native leptin biology and from unsupported cross-domain claims.

The article Leptin (116-130), amide, mouse: Precision for Energy Homeostasis focuses on reproducibility in metabolic research. This article clarifies the limits of extrapolating a defined peptide fragment to full-length leptin physiology or cardiovascular mechanisms.

Conclusion & Outlook

Leptin (116-130), amide, mouse is a defined peptide tool for testing selected questions about leptin signaling, energy homeostasis regulation, and immunometabolic biology. Its strongest immediate value is experimental control: the sequence, terminal modification, solvent profile, and storage instructions are specified. Its biological interpretation remains model-dependent because the product is a fragment rather than full-length leptin.

Future work should prioritize direct comparisons with native leptin, receptor-dependence tests, time-resolved pathway measurements, and stability checks in the actual assay matrix. The berberine study supports the importance of carefully separating inflammation mechanisms from reagent identity and does not justify assigning SIRT6-AMPK or NLRP3 activity to this peptide. A defensible conclusion should therefore state the tested model, endpoint, vehicle, exposure conditions, and controls.