This is a working overview of BDNF, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-04-24. Anything still debated is marked as such rather than presented as settled.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
| Property | Value | Notes |
|---|---|---|
| Appearance | White lyophilized powder | Typical for synthetic peptides |
| Solubility | Freely soluble in water | Also soluble in saline |
| Storage temperature | -20 C or below | Protect from repeated freeze-thaw |
| Analytical method | Reverse-phase HPLC | Confirms purity and identity |
| Common synonym | ACTH(4-10) analog | Reflects structural origin |
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
=== Lung toxicity === Some studies suggest that perchlorate has toxic effects against lungs (pulmonary toxicity) as well. Studies have been performed on rabbits where perchlorate has been injected into the trachea. The lung tissue was removed and analyzed, and it was found that perchlorate injected lung tissue showed several adverse effects when compared to the control group that had been intratracheally injected with saline. Adverse effects included inflammatory infiltrates, alveolar collapse, subpleural thickening, and lymphocyte proliferation.
=== 14 October === Five people were killed in an RSF drone strike on Debba in Northern State, while two others were killed in a separate attack on the Ad Babiker suburb of Khartoum. Seven SAF soldiers were killed in an RSF drone strike on Abu Jubeiha in the Nuba Mountains of South Kordofan.
== Relation to C-reactive protein == C-reactive protein (CRP) is an acute phase protein. Therefore, it is a better marker for acute phase reaction than ESR. While ESR and CRP generally together correlate with the degree of inflammation, this is not always the case and results may be discordant in 12.5% of the cases. Cases with raised CRP but normal ESR may demonstrate a combination of infection and some other tissue damage such as myocardial infarction, and venous thromboembolism. Such inflammation may not be enough to raise the level of ESR. Those with high ESR usually do not have demonstrable inflammation. However, in cases of low grade bacterial infections of bone and joints such as coagulase negative staphylococcus (CoNS), and systemic lupus erythematosus (SLE), ESR can be a good marker for the inflammatory process. This may be due to the production of Interferon type I that inhibits the CRP production in liver cells during SLE. CRP is a better marker for other autoimmune diseases such as polymyalgia rheumatica, giant cell arteritis, post-operative sepsis, and neonatal sepsis. ESR may be reduced in those who are taking statins and non-steroidal anti-inflammatory drugs (NSAIDs).
Salvia divinorum has large green ovate (often also dentate) leaves, with a yellow undertone that reach 10 to 30 cm (4 to 12 in) long. The leaves have no hairs on either surface, and little or no petiole. The plant grows to well over 1 metre (3 ft) in height, on hollow square stems which tend to break or trail on the ground, with the plant rooting quite readily at the nodes and internodes. The flowers, which bloom only rarely, grow in whorls on a 30-centimetre (12 in) inflorescence, with about six flowers to each whorl. The 3-centimetre (1+1⁄4 in) flowers are white, curved and covered with hairs, and held in a small violet calyx that is covered in hairs and glands. When it does bloom in its native habitat, it does so from September to May. Early authors erred in describing the flowers as having blue corollas, based on Epling and Játiva's description. The first plant material they received was dried, so they based the flower color on an erroneous description by Hofmann and Wasson, who didn't realize that their "blue flowers, crowned with a white dome" were in fact violet calyces with unopened white corollas.
Sources: en.wikipedia.org
== Signs and symptoms == Signs and symptoms of TIA are widely variable and can mimic other neurologic conditions, making the clinical context and physical exam crucial in ruling in or out the diagnosis. The most common presenting symptoms of TIA are focal neurologic deficits, which can include, but are not limited to:
The more hydrophobic the molecule, the more strongly it will bind to the stationary phase, and the higher the concentration of organic solvent that will be required to elute the molecule. The pore size has an effect as well. A particle with small pores would exclude large molecules from accessing most of the surface area on that particle. This means larger molecules would have lower retention time than smaller molecules, even if they are chemically similar otherwise. Many of the mathematical parameters of the theory of chromatography and experimental considerations used in other chromatographic methods apply to RP-LC as well (for example, the selectivity factor, chromatographic resolution, plate count, etc.).
==== Intracellular metabolism ==== Testosterone is metabolized in various tissues by 5α-reductase into DHT, which is 3- to 10-fold more potent as an AR agonist, and by aromatase into estradiol, which is an estrogen and lacks significant AR affinity. In addition, DHT is metabolized by 3α-hydroxysteroid dehydrogenase (3α-HSD) and 3β-hydroxysteroid dehydrogenase (3β-HSD) into 3α-androstanediol and 3β-androstanediol, respectively, which are metabolites with little or no AR affinity. 5α-reductase is widely distributed throughout the body, and is concentrated to various extents in skin (particularly the scalp, face, and genital areas), prostate, seminal vesicles, liver, and the brain. In contrast, expression of 5α-reductase in skeletal muscle is undetectable. Aromatase is highly expressed in adipose tissue and the brain, and is also expressed significantly in skeletal muscle. 3α-HSD is highly expressed in skeletal muscle as well. Natural AAS like testosterone and DHT and synthetic AAS are analogues and are similar structurally. For this reason, they have the capacity to bind to and be metabolized by the same steroid-metabolizing enzymes. According to the intracellular metabolism explanation, the androgenic-to-anabolic ratio of a given AR agonist is related to its capacity to be transformed by the aforementioned enzymes in conjunction with the AR activity of any resulting products.
Sources: en.wikipedia.org
Low-velocity: Less than 335 m/s (1,100 ft/s) Low velocity wounds are typical of small caliber handguns. They do not usually cause extensive soft tissue damage, and in the Gustilo open fracture classification are classified as Type 1 or 2 wounds.
=== Animal welfare issues and lawsuit === Panera Bread has been the subject of increased scrutiny regarding its animal welfare policies, particularly its sourcing of pork, dairy, and seafood. According to Reuters, internal documents revealed that the company has loosened its ingredient standards, allowing the use of some antibiotics in pork and turkey and permitting animal byproducts in cattle and chicken feed. Drawing on that report, a 2026 lawsuit by a food safety and animal welfare nonprofit alleged that Panera had misled customers about its animal welfare practices. The lawsuit claimed that Panera had marketed itself for its humane practices, including sourcing chicken from suppliers that provide sufficient living space for livestock, but that none of the chickens in its supply chain came from suppliers who met the standard.
==== Preventive trials ==== Failure of several drugs in Phase III clinical trials has led to AD prevention and early intervention for onset AD treatment endeavours. Passive anti-Aβ mAb treatment can be used for preventive attempts to modify AD progression before it causes extensive brain damage and symptoms. Trials using mAb treatment for patients positive for genetic risk factors, and elderly patients positive for indicators of AD are underway. This includes anti-AB treatment in Asymptomatic Alzheimer's Disease (A4), the Alzheimer's Prevention Initiative (API), and DIAN-TU. The A4 study on older individuals who are positive for indicators of AD but are negative for genetic risk factors will test Solanezumab in Phase III Clinical Trials, as a follow-up of previous Solanezumab studies. DIAN-TU, launched in December 2012, focuses on young patients positive for genetic mutations that are risks for AD. This study uses Solanezumab and Gautenerumab. Gautenerumab, the first fully human MAB that preferentially interacts with oligomerized Aβ plaques in the brain, caused significant reduction in Aβ concentration in Phase I clinical trials, preventing plaque formation and concentration without altering plasma concentration of the brain. Phase II and III clinical trials are currently being conducted.
While most hormonal therapy strategies seek to block hormone signalling to cancer cells, there are some instances in which supplementation with specific hormone agonists may have a growth-inhibiting, or even cytotoxic effect on tumor cells. Because many hormones can produce antagonism and feedback inhibition of the synthesis of other hormones, there is significant overlap between this concept and those discussed above.
Sources: en.wikipedia.org
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.
Peptidases degrade the compound within minutes in circulation. This short half-life is one reason nasal delivery is used, placing the substance close to the olfactory and trigeminal pathways.
No large multicenter trials have been published in English-language journals. The existing human evidence consists mainly of smaller studies conducted in Russia, which limits generalization.
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.