Thyreogen

1 Identity

Compositionally undefined animal-tissue extract. A low-molecular-weight peptide fraction obtained by extraction from animal thyroid tissue, supplied as an oral capsule. The originator's own label declares "peptide complex A-2, containing amino acids (glutamic acid, aspartic acid, tyrosine, L-phenylalanine, proline, serine)", which is a list of residues recovered on hydrolysis: a composition list, not a sequence, not an order, not a chain length and not a count of molecular species. Research-vendor material offered in vials under the same name is described variously as a short synthetic peptide, but no vendor discloses a sequence and no two descriptions agree. No CAS number exists for this article and none is quoted. Not synonyms: the same program's defined synthetic short peptides, each a single chemical entity with its own record, its own formula and its own mass.

Sequence

No defined sequence, and writing one would be a fabrication. The label's hydrolysis amino-acid list is the only compositional statement traceable to the originator, and hydrolysis destroys exactly the information a sequence carries. Any vendor document presenting a sequence for this article is presenting something the originator has never published. We state plainly that we do not know what is in this article, and no amount of testing on our side resolves that, because there is nothing to test against.

Molecular formula

None, and none can be stated. An extract has a molecular-weight distribution, not a molecular weight, so no single formula would be correct even if one were offered.

Average mass

None, and not determinable. The preparation is a mixture with no single molecular species, so no molecular weight exists to be measured and no reference standard can be constituted for a material with no declared analyte. Corroborating the absence from the supply side rather than only from the literature: a distributor catalog aggregating several major research-chemical supplier lines returns no product under this name.

Monoisotopic mass

None, for the same reason. A monoisotopic mass is a property of one molecular formula; there is no formula, so the computation has no input. Where this catalog prints a monoisotopic figure it is computed from a stated formula on the IUPAC 2021 abridged conventional atomic weights, and the arithmetic is shown; here there is nothing to compute.

Salt / variant note

Two directions of substitution, and only one is detectable by arithmetic, which is itself the finding. SIDEWAYS, within the extract line: every Cytomax A-series preparation is a low-molecular-weight peptide fraction from a different animal organ, none has a sequence, a mass or an assay, and the labels differ only in the organ word and the A-number. This article, A-2 thyroid, is interchangeable on paper with Vladonix (A-6, thymus), Sigumir, Ventfort, Svetinorm, Chelohart, Zhenoluten, Endoluten, Testoluten, Cerluten, Visoluten, Pielotax and Suprefort. No analytical result on any certificate discriminates one from another, because there is no measured attribute on which they differ. UPWARD, into defined molecules: the same vendors sell the synthetic short-chain peptides, which do have sequences and masses, and the two lines are routinely conflated. Vesugen H-Lys-Glu-Asp-OH C15H26N4O8 390.393 / 390.17506; Epitalon H-Ala-Glu-Asp-Gly-OH C14H22N4O9 390.349 / 390.13868; Vilon H-Lys-Glu-OH C11H21N3O5 275.305 / 275.14812; Testagen H-Lys-Glu-Asp-Gly-OH C17H29N5O9 447.445 / 447.19653; Livagen H-Lys-Glu-Asp-Ala-OH C18H31N5O9 461.472 / 461.21218; Cartalax H-Ala-Glu-Asp-OH C12H19N3O8 333.297 / 333.11721; Thymogen and Thymagen H-Glu-Trp-OH C16H19N3O5 333.344 / 333.13247. A certificate headed with this name reporting any of those masses is a certificate for a different, defined article. Two traps inside that list: Epitalon and Vesugen are 0.0364 Da apart monoisotopic, 93 ppm, and share an average mass to one decimal; Cartalax and Glu-Trp are 0.0153 Da apart, 46 ppm, and both round to 333.3. Note the direction of proof, which is the whole lesson of this record: a substitution into this name can sometimes be shown, but the correct article can never be shown, because there is no mass to match.

2 Class & testing panel

Form

Single article

Testing panel

P7 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

Literature exists for the program as a whole and is recorded by study type without any statement of what any preparation does; no study located was conducted on this named thyroid preparation as a characterized article. Program-level items, all reviews or animal work from or closely associated with one institution: Khavinson VKh, Neuro Endocrinol Lett 2002, PMID 12374906; Khavinson V, Linkova N, Diatlova A, Trofimova S, Stem Cell Rev Rep 2020, PMID 31808038; Khavinson VK, Kvetnoii IM, Bull Exp Biol Med 2000, PMID 11276315, rat; Khavinson VKh, Kuznik BI, Ryzhak GA, Adv Gerontol 2012, PMID 23734519 and Adv Gerontol 2013, PMID 24003726; Mironova ES et al., Adv Gerontol 2020, PMID 32593244. The evidence grade for the class is D, on the ground that it rests on animal and in-vitro work plus non-independent, largely Russian-language reviews from the originating institution, with no independently replicated randomized human trial located. The identity finding is prior to the evidence question in any case: with no declared analyte, no publication can be tied to the contents of a specific capsule.

4 Storage & specification

Storage

Oral capsules in the originator's sealed pack, 2-8 degrees C, kept closed and protected from light and moisture, handled throughout under this company's procedure for animal-tissue-derived material, with species and country of origin recorded on the goods-receipt note. The condition is set by the material type rather than by a stability-indicating method, since a preparation with no declared analyte offers no assay against which a temperature could be optimized; cold, dry and dark is the ordinary condition for a tissue-derived peptide fraction and it is applied from receipt onward.

Shelf life

The article is dated on the originator's own label date on the sealed pack, carried through unchanged; this company neither extends that date nor issues a longer interval of its own. No assay-based retest interval is set, because a retest interval is a statement that a lot still meets its specification and a preparation with no declared analyte has no analytical specification to test against. What limits the date is therefore the integrity of the sealed capsule pack and the 2-8 degrees C storage condition rather than a measured attribute, and any date presented as the outcome of a stability measurement on this article asserts a measurement that cannot have been made.