A Serum Tonic Factor In Foods (With Special Attention To Its Presence In Pineapfels)

[Amazoniac]

Some time ago I came across the following review:

- "Some Fruits, Including Bananas, Pineapples, And Tomatoes."
⬑ Phytoserotonin: A review

After more careful examination, on Table 1, the reference [72] for the serotonin content of pineapfels is the one criticized later on in the publication [15] that they relied upon to make Table 3.

[15] 5‐Hydroxytryptamine in Pineapples

"In view of the conflicting reports concerning the presence of 5-hydroxytryptamine (5-HT) in pineapples (Bruce, 1960; Foy and Parratt, 1960; West, 1960 [72↑]; Bruce, 1961), we have obtained the following results which we think will resolve the differences between Bruce, West and ourselves.

(a) Acetone extracts of the pulp of both unripe and ripe fruits contain a substance indistinguishable from 5-HT when assayed on the isolated rat uterus and rat colon preparations in the presence of atropine (10^-7). The contractions produced by both extract and standard 5-HT were antagonised by a specific anti-5-HT substance, bromolysergic acid diethylamide in a concentration of 2 x 10^−8-10^−7. There appeared to be more in unripe fruit (50 and 60 mcg./g.) than in ripe fruit (19 mcg./g.--an average of six estimations). A trace was also detected in stalk (0.2 mcg./g.) but none in the leaves of the crown (<0.08 mcg./g.) or base (<0.08 mcg./g.).
(b) Juice squeezed from the pulp of ripe fruits contained 5-HT in a concentration of 13-22 mcg./ml., an average of eleven estimations being 16 mcg./ml.
(c) Canned pineapple juice contained much less than this, and certainly nothing like the amounts quoted by Dr. Bruce (Bruce, 1960; 1961). One brand of Australian juice contained 3.5, 4,6 and 8 mcg./ml. and a Nigerian brand even less (1.3-4.2 mcg./ml.--an average of 2.8 mcg./ml. from six estimations).

There are three possible reasons for our previous failure to detect 5-HT in pineapple extracts (Foy and Parratt, 1960) and for the continuing discrepancy in the values for canned juice.

1. There may be an enzyme-in pineapple which destroys 5-HT, a situation already known to occur in the nettle plant (Collier and Chesher, 1956). But we have been unable to detect such an enzyme using a modification of the method used by Collier and Chesher.
2. Both fresh and canned pinapple juices are acid (pH 3.6-3.9). 5-HT is unstable in acid solution (Erspamer, 1940; Parratt, 1958), particularly when heated (Erspamer, 1940; Amin, Crawford and Gaddum, 1954). This would decrease the stability of 5-HT in acetone extracts of acid pulp and explain the lower values for canned juice compared with fresh juice.
3. Our figures for 5-HT are calculated as base. Dr. Bruce mentions “serotonin” (Bruce, 1960) and “indole derivatives” (Bruce, 1961). If his results are calculated using 5-HT creatinine sulphate as his standard then his published results would need to be halved. This would bring them more in line with the above results.

The likelihood of an erroneous diagnosis of a carcinoid tumour by pineapple ingestion is, in our opinion, small. It would surely be much more likely to occur in countries where the staple diet contains 5-HT, as in parts of West Africa where plantains (containing large amounts of this substance) are ingested regularly (Foy and Parratt, 1960)."​

Their points were ignored. I also didn't understand where the information that 'super mature' pineapples contain no serotonid was derived from, it would make no sense not to include it. But I digest.

Here's something useful for comparison:

[5] Serotonin content of foods: effect on urinary excretion of 5-hydroxyindoleacetic acid

"Plantain, pineapple, banana, Kiwi fruit, plums, and tomatoes had a high (>3.0 mcg/g) serotonin concentration (Table 1). The serotonin concentration of red (5.7 mcg/g), blue-red (3.6 mcg/g) and blue (43 mcg/g) plums were comparable and were grouped together.

Spoiler: Table 1

Ten fruits and vegetables had a moderate (0.1 to 3.0 mcg/g) serotonin (Table 1). The serotonin concentration of Haas and Fuerte avocados was seven times greater than that of Booth avocados (Table 1).

The following fruits and vegetables had a low (<0.1 mcg/g) serotonin concentration: strawberries, blueberries, raspberries, cranberries, pomegranate, persimmon, apple, crabapple, cherries, papaya, mango, grapes (Tokay), pear, peach, orange, tangerine, lemon, lime, kumquat, radish, carrots, green beans, bell pepper (red), cucumber, lettuce (Iceberg), asparagus, lima beans, corn, peas, soybeans, and peanuts."

"The following miscellaneous foods had a low (<0. 1 ıg/g) serotonin concentration: beefsteak (broiled), ham (baked), chicken (baked), fish (broiled), Parmesan cheese, corn, potatoes, rice, and wheat germ. The following beverages had a low (< 1 ıtg/ml) serotonin concentration: coffee, tea, milk, beer, and Chianti wine."

"Table 3 depicts the distribution of serotonin in various areas of fruit. The serotonin concentration of fruit peel is high in banana and plantain, but low in pineapple, Kiwi fruit, and tomatoes. The serotonin concentration is higher in the center area that contains seeds in banana and plantain but not in the seedcontaining areas of Kiwi fruit, tomatoes, and avocado. The serotonin concentration is higher in the soft edible edge of pineapple than in the less palatable center core."

Spoiler: Table 3

"Figure 1 shows that when seven normal subjects eat a conventional diet their 5-HIAA excretion is 4.8 ± 0.6 mg/24 h. When they supplement their diet with four medium-size bananas, their 5-HIAA excretion increases to 15.3 ± 0.6 (p < 0.01). After eating four bananas, all of the normal subjects have 5-HIAA excretion that is in the range found in patients with serotonin-producing carcinoid tumors; however, their platelet serotonin concentration (pmol serotonin/mg platelet protein) ranged from 631 to 1,835 (mean ±SEM, 1134 ± 200) with all subjects within the normal range of 300 to 2,200 pmol/mg."

Spoiler: Figure 1

"Table 4 demonstrates that dietary supplementation with black walnuts, pineapple, or plantain also increases the urinary excretion of 5-HIAA into the abnormal range. When the meat from 32 black walnuts was ingested, the 5-HIAA excretion was more than seven times greater than the upper limits of normal. The serotonin concentration of plantain probably remains high even after this vegetable is fried, for a volunteer eating two fried plantains plantains had a threefold increase in 5-HIAA excretion."

Spoiler: Table 4

"Although the urinary 5-HIAA excretion was markedly increased by ingesting serotonin-rich food for 1 day, there was no increase in the platelet serotonin concentration. This is probably due to the conversion of serotonin to 5-HIAA by the high levels of monoamine oxidase present in gastrointestinal mucosa and liver (14)."

"When normal volunteers ingested massive doses of serotonin (160 mg/d) for 5 days in the form of the pure chemical, there was an increase in both urinary 5-HIAA and platelet serotonin (14). Although it no longer appears to be a major health problem, at one time endocardial fibroelastosis was prevalent in Uganda (15). [I'm telling you, it exists.] Speculation was that the ingestion of large quantities of serotonin in bananas and plantain might have played a role in this endocardial fibroelastosis. There is, however, no evidence that moderate amounts of serotonin-rich foods have any adverse effect on the health of well-nourished people. The senior author, who incidentally is subject one in Table 4, continues to eat and enjoy bananas, plantain, pineapple, Kiwi fruit, tomatoes, plums and walnuts."

"Based on the weight of the edible fruit pulp or nutmeats in a medium-size specimen and the mean serotonin concentration of the fruit or nut, one would have to eat the following portions of food to raise the urinary 5-HIAA excretion 1 mg/24 h: one butternut or black walnut, one and a half English walnuts, eight pecans, one-sixth of a plantain, one-half of a banana, one-twentieth of a pineapple ☠, one and one-fifth tomatoes, two Kiwi fruits, two red plums or five and one-half Haas or Fuerte avocados. We therefore recommend that patients collecting a 24-h urine for 5-HIAA analysis avoid these foods. In contrast one would have to eat 10 eggplants or 170 filbert nuts to increase the urinary 5-HIAA excretion 1 mg/24 h."​

Now you have to find out if it varies depending on the fruit quality and the exact stability in case it's cooked.
- Relative Stability of Adrenaline, Noradrenaline and 5-Hydroxytryptamine subjected to Various Simple Treatments

 

[Amazoniac]

- Simultaneous analysis of serotonin, tryptophan and tryptamine levels in common fresh fruits and vegetables in Japan using fluorescence HPLC

Spoiler

You can also think in terms of mg/kg.

 

[Amazoniac]

For perspective..


- Role of serotonin in the hepato-gastro Intestinal tract: an old molecule for new perspectives

"About 95% of serotonin in the body is found in the GI tract, of which 90% is in enterochromaffin cells (ECs) and 10% in enteric neurons. The remaining of serotonin (5%) is found in the brain. As serotonin cannot cross the blood-brain barrier, the brain must synthesize its own serotonin. Virtually all of the serotonin in the blood is derived from the GI tract [20, 21]. Serotonin is present and synthesized in enteric nerves [22– 25]. Serotonin is present at high concentration in platelets, where it accumulates from the plasma by an active transport system and participates in aggregation of platelets and coagulation of blood [20, 21]. Though serotonin is present in the diet, most of it is metabolized before entering the bloodstream. In ECs and neurons, but not in platelets, serotonin is synthesized from the essential amino acid tryptophan by two enzymatic steps. First, hydroxylation of tryptophan by the enzyme tryptophan hydroxylase (TPH) (the rate-limiting step) produces 5 hydroxytryptophan (5-HTP). The second enzymatic step is decarboxylation of 5-HTP by the enzyme Laromatic amino acid decarboxylase producing serotonin [26] (Fig. 1). Platelets (and neurons) possess a high-affinity serotonin uptake mechanism, and platelets become loaded with serotonin as they pass through the intestinal circulation, where the local concentration is relatively high. Therefore, about 95% of serotonin found in blood is stored in platelets [27]. Serotonin in tissues can be very rapidly metabolized, mainly as a result of the activity of monoamine oxidase. In the kidney and the liver, the enzymes monoamine oxidase and aldehyde dehydrogenase convert serotonin to 5-hydroxyindole acetic acid (5-HIAA), which is excreted in the urine."​

- Sugar Responses of Human Enterochromaffin Cells Depend on Gut Region, Sex, and Body Mass (Fig. 4)

Didn't mean to repeat, concentrations vary depending on multiple factors including the part of the intestine being sampled, changing not only in relation to length position, but might also within a section and a cross. The search requires synthesis rate/quantification for 'whole body' or specific part. It's mandatory to add the 95% information if you're going to write an article on serotonin, but it's rarely discussed the amouts for it to be applied.


- Understanding the role of tryptophan and serotonin metabolism in gastrointestinal function

"About 1–2% of dietary tryptophan is converted to serotonin.[8]"

"Approximately 4–6% of tryptophan undergoes bacterial degradation yielding indole, indican, and indole acid derivates.[3,8] Approximately 0.5% of ingested tryptophan is excreted unchanged in urine.[8]"​

- Observations on the Release and Turnover Rate of 5-Hydroxytryptamine in the Gastrointestinal Tract

"[..]assuming that the 1500 g. of gastrointestinal tract contains an average of 3 to 5 mcg. of 5-HT per g. of fresh tissue[8], the total content of the gastrointestinal tract would be 4.5 to 7.5 mg. 5-HT. If the figure for the daily metabolism of 5-HT, calculated from the urinary 5-HIAA, is reasonably accurate (7.3 mg.), then a quantity of 5-HT corresponding to that contained in the entire gastrointestinal tract would be synthesised every 14 to 24 hours, that is, the half-life of gastrointestinal 5-HT would be approximately 7 to 12 hours."

"It may be seen that the above values agree fairly well with those obtained by Udenfriend and Weissbach[7], who used radioactive tryptophan and 5-hydroxytryptophan and found that in the rabbit the half-life of intestinal 5-HT was 11 hours."

"It should be kept in mind, however, that there is increasing evidence demonstrating that the biosynthetic possibilities of the enterochromaffin cells are far from being completely exhausted under normal conditions. Some experimental results, for example, seem to indicate that the turnover rate of gastrointestinal 5-HT may be conspicuously increased when excess dietary tryptophan is offered to the enterochromaffin cells. In fact, Lauer and others[16] and Kopinl[17] found that human subjects doubled their urinary excretion of 5-HIAA in the 6-hour period after oral administration of 5 g. of L-tryptophan."​

 

[Lejeboca]

Thanks for the compilation, @Amazoniac !
It looks looks like pineapples are full of serotonin.
I wonder whether there are any serotonin-antagonist food stuffs?

Going through

- Role of serotonin in the hepato-gastro Intestinal tract: an old molecule for new perspectives

I was surprised to see that:
"5-HT activates both intrinsic excitatory and inhibitory enteric mo-
tor neurons. It can stimulate cholinergic neurons to release
acetylcholine, which results in smooth muscle contraction,
or it can stimulate inhibitory nitrergic neurons to release
nitric oxide, which results in smooth muscle relaxation" (the quote taken from [11]) .

Serotonin may cause nitric oxide to release (I thought before that serotonin's effect on BM was only stimulating..)

 

[Dolomite]

It is interesting that the low serotonin foods also are low vitamin a foods.

 

[Cloudhands]

But without an increase in platelet serotonin, and an increase in excretion, does this mean that we dont absorb much of it? Or am i understanding this incorrectly?

 

[aniciete]

But without an increase in platelet serotonin, and an increase in excretion, does this mean that we dont absorb much of it? Or am i understanding this incorrectly?

Bump