Steroids hormones table

This mechanism is used by steroid hormones (Table 14—2), thyroid hormone, vitamin D3, and retinoic acid. 

Steroid hormones Cholesterol is the precursor of the five major classes of steroid hormones (Table 1). The synthesis of steroid hormones is initiated by the removal of a six-carbon unit from carbon 20 of the cholesterol side chain to form pregnenolone, the common precursor of all steroid hormones (Fig. 5). A series of reactions catalyzed by cytochrome P450 modify pregnenolone to give rise to the individual hormones (Fig. 5). 

The micelle/water partition coefficient for many solutes have been shown to correlate to the octanol/ water partition coefficientJ ° Data in Table 8, from Azaz and Donbrow, show that the micellar partition coefficients of the methylphenols increase with the number of methyl groups. Collett and Tobin showed that the micellar partition coefficients of several benzoic acid derivatives are proportional to their octanol-water partition coefficient for poloxamers (Table 9). Tomida et al. also illustrated that most of the 34 monosubstituted benzoic acids with Brij 35 have micellar partition coefficients that are inversely proportional to their aqueous solubilities and proportional to their octanol-water partition coefficients. The data of Tomida, Yotsuyanagi, and Ikeda[ °l for some steroid hormones (Table 10), further illustrate the parallelism between octanol-water and micelle-water partition coefficients. 

Some plant and animal steroids occur in large quantities and can be used as inexpensive starting materials for pharmaceutically useful steroid hormones (see table 22). 

Most of these enzymes have steroids or fatty acids as their substrates (Table 1). Many P450s in endogenous biotransformation pathways are characterized by usually very narrow substrate and product specificity and by tight regulatory systems, especially those involved in steroid hormone biosynthesis. 

Table 1 Summarized table with the more important PPCPs divided into antibiotics, steroid hormones, and other drugs. Their generic chemical structures and the use or origin are shown. Some reported data regarding their environmental occurrence and the more probable environmental fate are also given... 

Table 5 Most important natural and synthetic steroid hormones ...

Table 6 Immunochemical techniques developed for the detection of steroid hormones... 

Steroid hormones are produced by only two tissue types, the adrenal cortex and the gonads. A summary of the steroid hormones is given in Table 4.2. Steroid hormones are synthesized from cholesterol (Figure 4.2). This sterol lipid may itself be synthesized within the steroidogenic cell or it may be delivered to the cell by circulating lipoprotein complexes such as low density lipoprotein (LDL) or high density lipoprotein (HDL). 

The steroid hormone receptors are sequence specific DNA binding proteins whose cognate DNA elements are termed hormone responsive elements" (HREs). The HREs known to date possess a common structure. They are composed primarily of two copies of a hexamer sequence. In table 4.1 are listed the hexamer sequences of the HREs of important nuclear receptors. 

A further, more dramatic difference to the steroid hormone receptors is the localization of the receptors. The receptors for the retinoids (RAR and RXR, see table 4.1), the T3 hormone (T3R) and vitamin D3 (VDR) are mainly localized in the nucleus and their activity is not controlled by the heat shock proteins. The receptors also bind the corresponding HRE in the absence of hormone, in which case they can then act as repressors of gene activity. In the presence of the hormone an activation of gene expression is usually observed. 

The 13C chemical shifts of selected androstanes, pregnanes and estranes are given in Table 5.10. The formulae of the parent compounds and some related steroid hormones with numbering of the carbon atoms are given below ... 

The assignments of the aromatic carbons in ring A of estrone were performed by comparing the 13C NMR spectrum of the steroid hormone with that of its acetate. A correlation with the acetylation shifts of phenol (C-l (3.7 ppm) C-2 (6.2 ppm) C-3 (0.6 ppm) C-4 (4.4 ppm)) resulted in the signal assignments outlined in Table 5.10. 

Steroid hormones have a variety of important functions, including regulation of carbohydrate and mineral metabolism and development of secondary sexual characteristics (Table 20.4). Steroids are often used in the treatment of diseases such as arthritis. Some athletes use steroids to promote muscle growth. 

The step-by-step synthesis of the steroid hormones pregnenolone and progesterone from cholesterol (C27) was presented in chapter 20 (see fig 20.22). Note that pregneno-lone (C2i) and progesterone (table 20.4) (C2 ) are intermediates in the biosynthesis of all of the major adrenal steroids, including cortisol (C2i), corticosterone (C21), and aldosterone (C21). The same two compounds are intermediates in the synthesis of the gonadal steroid hormones, testosterone (C,9) and 17/3-estradiol (CI8). Because the synthesis of all these hormones follows a common pathway, a defect in the activity or amount of an enzyme along that pathway can lead to both a deficiency in the hormones beyond the affected step and an excess of the hormones, or metabolites, prior to that step. 

Table 12. The influence of l-(chloromethyl)silatrane on the endocrine functions regulated by steroid hormones...

Table 23.3 lists recent publications concerning SPCE-based approaches towards the analysis of the naturally occurring compounds ascorbate, steroid hormones (including progesterone and estradiol) and protein hormones (hCG and insulin). 

Similar to neurotransmitters, steroid hormones are classified as either agonists or antagonists, as in the following table. 

Corticosteroids have been useful in the treatment of acute leukemia, lymphoma, multiple myeloma, and other hematologic malignancies as well as in advanced breast cancer. In addition, they are effective as supportive therapy in the management of cancer-related hypercalcemia. The steroid hormones and related agents most useful in cancer therapy are listed in Table 55-5. 

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